It's as simple as it is, go into Local Versus and press enter to configure the bindings when you do get there press Backslash \ <--- That (this is the lp button for players 2) now the all config will show up allowing you configure your keyboard for player 2 do not use any of the keys player 1 uses otherwise it'll all be a mess and you'll have to start over.

For an example on Key Binds here is what setup I use

For Player 1

WASD for movement, U I O for Punching Buttons, J K L for Kicking Buttons everything else you can set to whatever you want.

For Player 2

Arrow Keys for Movement, 456 for Punching Buttons, 123 for Kicking Buttons, again everything else you can set on your own.
(if you so choose, you can also do 789, and 456 instead.
take note to have Numpad on if none of the punching or kicking buttons work.

I hoped this guide helped you all do that local 1v1 match stuff
if you have any problems please leave a comment and I will do my best to support you in anyway
Thank you for reading this guide and have fun.

As seen from the comments section, A Latin American keyboard has a backslash, but if you change it to work as an English one, it should work.
anymore notes regarding these will be put into this section.

the key that emulates backslash in the Latin American keyboard is ' } ', not the Latin American backslash

Gaming Keyboards do not tend to ghost out. (allowing multiple key presses at once) So you can just use one keyboard and not 2, but it would be a little cramped if two people were using the same one.