I like that you made a multiplayer game! I don't have anyone to play with so it's a bit difficult for me to assess how fun it is, but I can see how it could be fun lol. The vibe reminded me a bit of Smash Bros and Jump King put together.
I think it would be cool to have an indication that the frog is charging up his jump - for example, the frog quickly crouches down a bit (unless this was a deliberate design choice to keep the charge hidden from the opponent)