How can I switch "numbered" and "normal" type of sub-lists?

How can I switch “numbered” and “normal” type of sub-lists ?

I think in the Menu or Ctrl+Shift+X on the parent-node of the sub-list.
I hope this is what you meant.

Yeah, what Philipp said. Or you can do it manually by clicking the hamburger menu button on the left-hand side of the parent node: