Can't the mens be followed by the verb in Norwegian?
As in "She plays the piano while singing songs"? No, I can't find a way to say that and keep "mens" in the sentence. You need the object as mens ties two complete sentences together.
I mean, in some other Germanic languages "but" is followed by a verb, would that work in Norwegian? (I'm new to Norwegian, most of my knowledge is from Swedish so far.)
'men' and 'mens' have different functions. 'men' can be followed by a verb in a few cases, but not usually.
"(...), but isn't that weird." = "(...), men er ikke det rart."