Bad Thoughts wrote:
SecondSecondmirror-universe equivalent of the UFP does not exist in the 24th century in the mirror universe. That would create another thematic paradox, perhaps one that is deeper.
I feel like you're missing the crux of the mirror universe... it's just one among an infinite variety. Calling it THE mirror universe is poetic rather than scientifically descriptive.
Infinite mirror universes give plenty of narrative license to have an infinite number of different Picards cruising around in Star Trek: Frontiers.