Also one thing to remember is that you are developing a game, not creating an animated movie, so you do not need to use 1 million frames for each animation.
Ah, of course not. *lol* But in Germany we say "Kleinvieh macht auch Mist", so if you have a lot of small animations you will have the same huge size at the end of the day.
I don't know this webp and I think, none of my cut- and picture tools I use supports it. OK, I haven't the newest programs. Maybe it's in Gimp, I haven't check it yet (I hate Gimp...).
I don't change png into webp in my test games, but I'm looking for a converter tool for the next project. This 2500x2500 thing was only a mini game to test how scrolling works; it's not my favourite way to work... Usually a typical scene is only 1024x720, 800 x 600 or something like that, so my animations and poses don't need huge resolutions... ;-)