I am the same not a huge fan of the football games but this is a lot of fun and its got a lot of potential. Sad indeed if keyboard and mouse is not supported. But nowadays i guess everyone has a controller of an xbox or ps4.
Yes you can change it :) If you don't have a controller, it should use keyboard for player 1 by default.
I'm not really a discord kind of person, the problem with too much input is that it takes time away from actually working on the game, so I'll keep to listening to comments here, and on reddit (I post an update there every new version) :)