Where the Saturn felt like it was a 2D virtuoso, when it came to 3D you‘d often think "wow, it’s trying its best!" and quite often the result of that would be neat, interesting, weird, curious, beautiful, odd, etc.
Likewise on Playstation the 3D almost felt effortless, though of course it wasn't, where higher end 2D games often made one think "wow, it's trying its best!"
I want to talk about some of the Playstation exclusives - not arcade ports, or games that also came out elsewhere - that pushed 2D, either fully or in part, to interesting results. There's kind of a unique vibe there, which we might get at through this discussion. To me the way the Playstation does transparency is quite different from any other console, so that's a defining factor in my mind. I'll start with just a few.
[**NOTE**: since folks already started posting ports I'm gonna say if you really want to put a port out there make sure it's got unique features on the ps1 and tell us what is unique about it!)
Gear fighter dendoh. Really neat 2D beat em up stages followed by 1v1 3D fighting segments. Lots of moves, really fun and fluid to play.
https://youtu.be/bV4FhvF4Q1I?si=VAvmWcTDjjFP93An
Chippoke Ralph no daibouken - Little Ralph's Big Adventure. No long play will show this but it's a very branching path sort of game with secrets galore. I just wish it were a little easier on normal mode, one hit kill is a little hardcore for me. Super fun though, and again 1v1 fighting battles for bosses, but still 2D this time. It's more fun than it looks on replay.
https://youtu.be/io9pntL1nL8?si=ZJL5Xah_pEnLN_Q7
goemon shin sedai shuumei. It's the weird 2d sidescrolling goemon that apparently people don't like. But look at it! It's weird! It's trying its best!
https://youtu.be/uPG3iSlxPF4?si=5MAUbEF1qRAoP4qf
Adventures of Lomax. I don't own this one and wish I did. Just a pure pixel tour de force, the last gasp of the bouncy pickups, over animated, strangely laid out Amiga dream. (whoops this also came out for windows but we all know that doesn't count)
https://youtu.be/lJfevgKSa0w?si=7GXw-88bguSgqChA
Philosoma. Mostly 2D, sometimes 3D perspective shifting shooter - it moves from vertical to horizontal to behind the back to semi-isometric alongside an ambitious script (continued in Phase Paradox). People didn't like it at the time but it's neat and weird.
https://youtu.be/aQOrs1s8zFE?si=Cu4A5BfZC9DKT4n3
Metaphlist. Weird omnidirectional shooter where your shots can basically grow to infinite size. Just bizarre (click around the 1 hour 49 minute mark and you can get a taste).
https://youtu.be/grAE4Y8jF5M?si=DIGDgIeGoMs_wr_z
Alundra! It's Alundra!
That's where I'll start for now. Any fun ones you've got, especially lesser known ones, do drop them here!