Lord Henry is already useless like a useless thing, so he'll keep on being ... useless. So he's mostly there to react to his superpowered friends, if you want him.

Una: well, her main power was already sort of defanged to begin with, since her time machine doesn't really work in this setting, so there's not much changing with her either. But she'll volunteer for any attempts to Do Something, so there's that.