Justin Gombos wrote:
Suppose a US certificated pilot is in Europe for a couple years, and
the flight review becomes due when they're there. Does it complicate
the process to get the review in the US months or even a year after
the deadline? I'm figuring my chances of finding a FAA CFI in Europe
isn't something I can count on.

You might check with AOPA. I'll bet they have a list of US CFIs who can do a
BFR overseas.