Why does it have to be a specific tutorial? I mean that would obviously be right to the point for you, but in the end it will use the same actions shared between all types of games. For example triggering animations, moving game objects, enabling/disabling collision boxes, etc.
If you can't find anything specific by searching, just search each piece one by one or watch some general tutorials to get an idea behind the logic of making things.
For example I've never tried to make a beat em up, but I would do the punching and kicking by making a collision boxes which are children of the moving character. The punch button would trigger the animation and then turn the box collider on for a brief moment. The same FSM could then disable the collider, or maybe the collider itself could have an FSM which shuts itself off after a Wait period or detecting that it hit. The target would then have an FSM which detects the collision and triggers it's hit animation and adds to an Int for health. This is not that much different than my current VR shooter where a projectile has a collision box that hits the enemy... which is not that much different than running into a health kit in a side scroller... etc.
