"Who else is coming?"
Translation:Hvem andre kommer?
Should I not be able to also say "Hvem annet kommer"? "Who" can refer to one person, as well as as more than one. In fact, because the English sentence here uses the verb "is", I would argue that the subject must be singular, and so the correct translation should be "Hvem annet kommer". And "Hvem andre kommer" should really be translated as "Who else are coming".
Not a native speaker, but isn't "annet" neuter? So you wouldn't use that form for people. According to the UIB dictionary, "andre" can be used instead of "annen" in all forms though :) https://ordbok.uib.no/perl/ordbok.cgi?OPP=Andre&ant_bokmaal=5&ant_nynorsk=5&begge=+&ordbok=begge