When playing siege with my 2h + danish, I tend to switch to halfswording when on the walls/corridors. It's quite a bit shorter, slower and weaker, but it's better than hitting the walls all the time.
Personally I'd like to see it use 2h wpf, it's a little strange that it uses pole wpf tbh. If it got that, it'd be fine imo.
Trying to think of 2h's with secondary modes that actually use 2h wpf.
I think it's just the new one on the Persian axe?