[sargram01]

Actually I think it should be ok, because you’d enter the name in the nomative case and then when you write it on the screen you’d declinate it based on the language you’re displaying it in, which would be the same for every name regardless of its origin.

[Piskvorrr]

Tried that once. Horrible, terrible, no good idea. (The only rule you can be sure of is "there are countless exceptions, and exceptions from the exceptions", everything else is a minefield in a quicksand) Asking for "how should we address you" is far easier, even if a few users fill in "Your Galactic Imperial Majesty".