Could I use a keyboard for mashing, overflow, battles etc. and another key board for wall humping and wall humping speed boost in the 2D room ?

PS: My first keyboard can't wal humping and the second keyboard isn't optimezed for mashing.

Multi-client refers to having multiple instances of the game open. It's always been permitted to use multiple input sources, some runners used to opt to run with keyboard + controller.

thanks you