How to change player look

So I’m still making a game and I have gotten to the point to where I want to import a new player character. So basically I want to take that Robot one that is just a placeholder in UE4 and replace his model with someone else, so I save time and dont have to copy all of the blueprints and stuff again

Simplest thing: Import a new FBX model that uses the same skeleton.

Or, export the existing robot model(including the skeleton), edit the model so it looks how you want it to be, then re-import it.
in the player character object, just select the new mesh and you should be good.
this way all you do is change the model.