Uhm... there's a TON of axes in Valheim. Not sure what you mean with "one handed battle axe", if the black metal axe is not good enough for you.

Ok, no chains. I have no idea how these would look like and how they would work as I don't know the vinland saga.

Edit: Are you talking about different skins for basically the same weapon? My apologies, I'm trying to understand.

Edit2: In regards to combos: Most weapons do have a secondary attack.