BimmerDude And Homer just added it, for which I thank him.
Great even for motorcycle diplomatic plates. They exist, but fortunately follow the same format. Trailer plates exist as well and follow the YY NNN-L-AA(A) RR (Y = year digit, N = serial digit, L = letter, A = embassy digit, RR = region code) format.
I wonder why don't motorcycle plates do the same with regular plates akin to North Macedonia, Croatia and Bosnia and Herzegovina, but if the problem is four serial digits, the first serial digit can casually be stashed at the top next to the region code and coat of arms