In terms of platforming, Celeste is hard to top. But admitted : when talking beat em ups... That ain't one.
Guacamelee 1 & 2 certainly deserve mentioning. It's a bit metroidvania, but hardly maze - like. You collect mostly Mexican wrestling combat moves... That's also the theme, BTW. The story is light but fun, combat is decent (though the first one takes a bit to get going) and there's plenty of variety. It's...on every system you don't own, apparently (oops). But okay, it plays on a two-bit computer as well.
On the SNES, definately try out final FIGHT 3 (edit : only now noticed I wrote final fantasy by accident
) if you've got the chance. It's not really a platformer (unless you call "going right except when you smash open a door" platforming), but it packs a punch in the "beat your fellow human into the ground" department.
Turtles in time is the more classic answer, from when konami still made good games. It's also 2.5D with a minor in platforming and a major in cowabunga-ing.
Then there's lost vikings 1 & 2. These lean (much) more on the puzzle side. You basically control three dudes: one that can run, dash and jump, one that carries a shield and can paraglide, and one that has sword and arrows and is only in the first game because marketing said they had to have some action in their game. Okay...I'm exaggerating a bit, but the combat is a bit stale compared to the tactical nature of it. Back from when blizzard wasn't known for their craft franchises.
On the GBA platform, I only know Mario vs Donkey kong. Yeah, sorry: I'm more of a sucker for puzzle platformers, so...erm...perhaps ninja-five-O ?
If you've skipped over my last paragraph you want to dismiss my PS1 suggestions as well, as they all consist of Abe's Oddyssey and more Abe's Oddyssey (and Exoddus, I presume...Not played that one to proverbial death).
I...think that's about it that I know of. Of course there's the classic double dragon series (latest is neon, isn't it?), but...to be honest beating enemies and jumping chasms doesn't gel well with me (or even with the industry).
I mean...okay, the pang series, for example (it has an entry on SNES...I think it's called buster bros, though). That one has action (you're shooting bubbles) and platforming (climbing ladders and so on). But it's still considered more a puzzle platformer than an action platformer. Should that spark your interest?