I see. Well, thanks for offering to help. Hopefully we'll be able to see more and more stages get ripped some time in the future.

@EmRuHire Ripping stages is possible and I think as easy as any fighter's model. I ripped some for myself to see how they are and also imported one time the animation idle of Final Destination.

The only reason I don't try to post them here is that I don't have my mind into doing it and hoping that the sended models would respect the requirements of this site. I asked in the comment section of Monster Hunter World if I can help, but even with the nice answer from Peardian (thank you again) and the already shared models, I didn't find the courage yet to rip a model, preparing it up almost blinded and then send it and hope that maybe I didn't do anything wrong.

So, all I can say to import the models you want is to get the base models files and one of the two importer addons for Blender, import them and set them up to your liking in Blender or any other software of your liking (in this case, import in blender then export them in fbx or else and import it in the software you want).
Here are the two pages where you can find the different addons:
https://gitlab.com/Worldblender/io_scene_numdlb (old one, I used it for the stage models)
https://github.com/ssbucarlos?tab=repositories (newer and surely better than the old one as it can even import modded models in Blender)

Hope that helps. Note that there is maybe easier options than the one I said.

@WarGrey: I don't think sculpting an entirely new mesh for a facial animation is lazier than morphing/animating an existing mesh. Mesh swaps were likely chosen for the sake of resource efficiency, minimizing the amount of bones/morphs required for the engine to handle per character without sacrificing expressiveness of the models.

The main issue isn't the rips, they are perfect, the main issue how lazy the developers are for the longest time.
They should stop with model swapping already and use blendshapes for emotions and all that jazz. So we can at least have models that doesn't suck to make them work. Seriously models are amazing since Brawl, I love the texture work and topology in these models but having to remove bunch of useless mesh so I can use them in, say, VRChat, is just terrible. Especially with models like Pikachu. You can just rig around the lips to make him talk and stuff, it's easy why model-swapping why? Gah.

Y'all say Kirby needs every one of his hats grouped with him but Melee and 64 literally had separate categories for hats and Brawl, 3DS and Wii u don't have them anywhere
EDIT: All of Brawl's Kirby hats in Brawl are up and I have a few pending on 3DS and they're separate. I don't know if that will still be the case in Ultimate, considering how much there are but it would be consistent

It sucks to see so much of what's ripped for Smash Ultimate, whether that's the fighters, the assists, the Mii costumes, the items, and even the stage elements, but then scrolling all the way down to see that barely anything has been done with the stages themselves.
I sometimes always want to find assets for a stage and coming out with nothing in return. I get that it could be pretty difficult to rip an entire fighting field and make it accessible to everyone with no errors, so I won't really argue about it.
I have been considering uploading to Resource from time to time, though, most of what I seem to see not ripped yet on Resource is what I'm most likely gonna have to rip myself if anything. Which is fine, I'll do what I must. It would be a little strange to be deemed as "The Stage Ripper" if that's what I'm mostly aiming for.

a real downside of ripping more recent games is all the different items and expressions being clumped together, not only making models messy and hard to get default polygon counts for, but also lags model viewing software

may be too much to ask but i think it would be a good idea to include an extra file with just the character with default expressions, or better yet, the items individually too

PS : Sorry for the late answer...

@AmyHopps10 After searching to remind myself how to do it, here's the tutorial that tells you how to separate the PRM image to desired material: https://www.youtube.com/watch?v=lisp713k38s
If you still don't really know or didn't see it in the video, use a software (like Blender) to separate each channels (RGB or RGBA if it has alpha) from the PRM texture. In Blender, in the shader editor, just do like the guy do in the video, use the "Separate RGB" on the texture.
Also, here are some videos from an amazing guy who can help you with knowing how these material works and how to find which one is used for each type of information, and also about other subjects:
https://www.youtube.com/watch?v=QcTApanvYEg
https://www.youtube.com/watch?v=vANLudW371k
https://www.youtube.com/watch?v=dX-LvaB36yk

@MarioFan2324 Yes he is (specifically, Green Hill Zone). Same with Knuckles and Silver.

Im pretty sure but I might be wrong but I think tails is in the sonic backround?

take a quick look at where the ink bullet is hitting bowser in the thumbnail...

How did you convert PRM maps to separate rgh/spc/mtl maps on these models?!

I would try to rip & submit the Paper Mario stage but given my track record for non-custom models having one thing or another wrong with them every time, I doubt it would be successful, also the environments are completely flattened in their raw format due to in-game being loaded in with an "unflattening" animation. Fixing that manually would probably invalidate the integrity of the model, but not fixing it would make the model be unsuitable for basic use without first scaling it thousands of percents on one axis.

@JJ314 I don't think so, before Sora was confirmed to be the last fighter, I remember someone previously said on this page why Kirby wasn't ripped, and one of the site admins said that it would be hard work, due to all the hats must be included with his model and had to wait until the last fighter is announced.

Couldn't it just be Kirby (Base Model) then all the hats separate (like the other games)?

Kirby can finally be released after all this time

Since Sora's the last fighter, wouldn't this mean Kirby can be finally ripped?

Sora is in the game now, but its gonna take a bit...

@AmyHopps10 Because ripped models needs ajustements. For example: missing mesh; mesh that had lost some bones weight through extraction process; and in the case of ultimate, separating the normal map, roughtness, metalic, ink pattern (when a character gets inked by inkling or when it changes into metal). If they send the models roughtly ripped, it will be a nightmare to people who doesn't know how to fix or can't fix these stuff if they just want to use it simply. If you want to animate a model and you see that some bones aren't connected to the part they suppose to move and that the textures don't show the model like it means to, then you'll stop or spend hours to find a way to fix it all at your tastes.