Slitherine

I think it would be a great feature to allow two unit that have not moved to swap position (this would exhaust both unit movement points).
Indeed, in some situation this is clearly an interesting move and it is impossible to realise.
I don't see any good reason to deny this kind of movement.

I concur this is being implemented in many recently games: SC WW1, Time of Fury (not released yet)... and it's very handy.

ahh... you revealed a secret of TOF.

Yes, swapping is most important in MP games as units become bottle necked. You need to rotate units but can not.
Hence.. you are screwed.

It wont work well in PzC because units can only move once. You cannot go back to them so swapping would use both units move up and I dont think it would actually be very useful in practice. I think the time can be spent on other more interesting improvements.