Defo no need to prove IFR currency other than the 12th month check on part 91 (private ops) - BUT that is TYPE specific in EU land though, as in on the actual type - not accepting 24 months if you do it on a "similar" type. That being said, I don't know if complying with the aforementioned FAA 24 month rule for IFR currency would hold the "waters" in a SAFA check.