I fired up the demo again without my gamepad and there seems to be full keyboard button mapping for four players in the options menu. You should probably try the demo for yourself.

You can.
There's a 360 option for aiming but you'll only get that on a controller.

Only actions. Directional controls cant be redefined. WASD

I'm looking for a configuration file to map controls to the keyboard for 2 players including directional keys because I want that on an Arcade Legends Ultimate with JoyToKey for 2 players. But currently, I'm clueless about how to do that. It seems Wayforward forgot about providing a complete configuration menu for such purposes. Recently I played the new Iron Meat perfectly mapped thanks to the ingame keyboard configuration.

Gosh, it's an arcade game. The game even forgets the action button configuration for player 2 after loading it up again and I can't click P1 configuration after switching to P2. It feels not polished. There isn't even a CRT filter to create an authentic arcade look. But thanks to ReShade CRT-Royale I can do it.

It would be a feature request to be able to map 2 to 4 players to a keyboard without using a gamepad for using controls of an Arcade cabinet. The game is fun, I want to play it oldschool.