I just use UMG widgets. If you want a touch joystick or swipe/drag kind of analog controls, you can program those yourself using the Touch event.
I have had a good time using the Ultimate Touch Components I got from Unreal Marketplace to place a joystick on my touchscreen and have it move well, but I created and programmed my own UMG widgets for the action buttons.
I remove the built-in default touch user interface that comes with Unreal because it doesn’t meet my needs (this can be done in the Project Settings)