... tutorial
For Foxtail_productions
So, first, double tap on the frame you want to get it like this:

Tap on the transitions icon (blue magic wand-looking thing. First one after trash can aka mE)

After you add the transition, you can freely adjust it using the arrows on either side of the highlighted segment. Drag either arrow from left or right to change the length of the transition.

There ya go!
Hey, if anyone has any questions about CuteCut, you can ask me :>