Why does "møtes" end with an "-s" instead of an "-r"? Is this a different tense? Aspect? Mood?
It is a reciprocal verb, the "-s" means "each other".
Vi møtes = vi møter hverandre ? Are they interchangeable?
They are interchangeable for sure.
From my knowledge, they are interchangeable.
Ahhh, I see. Tusen takk! :D
Verbs ending in -s are often passive, but in some cases the meaning is closer to using a reflexive verb. In English, you could also say "until we see each other again". See also the expressions "vi ses" and "vi snakkes".
It's a different voice.
why "Til vi møtes igjen" not "til møtes vi igien" , I mean the verb in the second position .
It's not a full sentence, it's a subordinate clause
That applies to stuff like adverbs. Conjunctions are different.
Is this something a native Norwegian would say, or just a literal translation?
Don't know where, don't know when.
First thing that pops in to my head when I hear this phrase:
First thing that popped into my head was "And if we shall meet again,
Why we shall smile" from Julius Caesar lol
Lykkelig stier til deg...