I can confirm this happens with pretty much any skill that can only be performed once in a turn. So Overwatch, firing mounted weapons, Boom Blast, Onslaught, etc.
For someone who reloads a lot (I like to play out different strategies and really optimize my way through a turn or a mission) this is very game breaking.
The enemies all skipping their turn also makes this worse, as you will often unintentionally trigger this exploit. Here’s hoping a fix is with us soon!
And it’s STILL broken. Well, except no enemy moves part, enemies move alright. It’s just me being unable to use any use-once abilities after save-load.