Transition Help

What is the name of this transition, I know it can be replicated easy but I would like to know the name of it. I have seen it before but unable to find it now... Does Anyone
know

Don't know if there's an official name for it, but you're just flashing between clip a and clip b as a transition. There are more than one in this section if you look. I have created it myself, but don't know that I've posted it anywhere. I may have to do that.

You could do this manually very easily. Clip A or Clip B needs to be superimposed above the other. The one on top, you just use the blade tool (command- to cut a frame or two out ever so often.

there is an actual name for it, it was in one of those free plugins/transitions for fcpx,I just cant seem to find it. Post the one you created

That effect can be done with the FREE STROBE effect by Nocommotions. You can get it by downloading his Template Master program. He has many free and also paid effects, titles, transitions and generators bundled nicely into his Template Master program.