Got a few buff ideas
UpB is weird? Like unlike all the other upBs, you can't walljump out of it. You have to airdodge to get out of it, THEN walljump, so if you used your airdodge already, you're kind of stuck, which sucks because the move obviously doesn't go up very far.
NeutralB also needs a small fix. A lot of times, since rivals stages are so small, no matter where I use NeutralB, I get punished for it because the animation is so long, and then from that punish I'm comboed for most or all of the buff's duration. 3 possible fixes I can think of, or a combination of them.
First is to make the buff last longer, so even if you are combod, you have more time to use it after, but that's not a great fix.
Second would be to give the Beasts a hitbox when they appear, which could be cool, kind of a style thing, like hitting someone with Shovel Knight's taunt.
Third is to make it so the Beast still appears, but the Ranger has either no animation, or a much shorter animation. That way you can summon, the Beast appears, showing which buff was taken, but you can get away almost instantly after. This would also allow people to use Suicune before dying. Currently if you use a Beast midair, you're losing too much height for it to be worth it, and that's only if you don't die entirely from how far you fall.
Also for neutralB, might be a good idea to have a timer next to them at the bottom to show how much time is left on your buff. It's not always easy to tell based on their outline.
One more thing with neutralB, this could just be me after playing SK a lot, but it might be a good idea to reorder the Beasts in their menu to Raikou, Suicune, Entei, and have the cursor start in the middle on Suicune. That way it's a lot easier to remember middle for Suicune, left for Raikou, right for Entei. I know currently you can still reach Entei in one input by the cursor moving left and wrapping around to the right, but with how it's formatted, it's a lot harder to remember, and you end up moving right twice instead most of the time.
Last idea, does upair have a final, launching hit? You'd think it would, like Maypul's or SK's, but I feel like I never get that final launching hit, like the last hit just flinches like the other hits in it. Just kind of strange.

Hope this didn't come off as forcing my ideas too much, this character is really well designed and is super fun to play, just a few things need some changing.
(Oh also please write their information in game, because they actually have an important gimmick)

thanks a lot for this feedback!

i will look into making the beasts less punishable in some way
u-air does actually have a final hit, yes, i could make it slightly stronger perhaps
up-b is weird and im not currently sure how to make it so you can walljump out of it but im looking into a fix because i don't like that either
the order of the beasts may be changed if that is something that people want
i will look into implementing a timer as well

what exactly do you mean by writing their info in-game? do you mean in the description in their config.ini? (like, the description that shows up for the character when viewing them in the workshop section in extras)

Honestly there's so much work put into this that shines through that I hate to be this guy, but you cannot have a character whose every single move is that they stand still with a small hurtbox and have a massive hitbox extend from them that cannot be hit. If the Pokemon in some or most cases were treated like part of his hurtbox he'd be pretty fair, but as he is, he's too easy to ledge guard with, too easy to just push buttons as and hit, and way too hard to punish for sloppy play.

Specifics would be that having Side B having infinite untech time is way too strong for a shot that fast. Dair is actually rather weak because he falls so fast and it takes so long to come out that it only comes out if you do a full jump. Up B has a really awkward hitbox that just sort of radiates every couple seconds.

That said, this is such a cool character. All the sprite work is really well done and the general concept is fun to the point where I wish a Pokemon trainer actually played like this.