So do they fuse with their host like with bats or do they sting?

They fuse like bats by biting. Their stings are just a mild sedative

Ah thus the tiny bee butt wings lol

Aside from being bumbling fluff bugs has anything ability wise been lost in the transition from Succubat to Cherubee?

Cherubees have a more specific body type that they give hosts, like they can't result in tail maws for example.

Hosts are less thoughtful about what's right, like, by necessity. They think how to accomplish their goals, not about what their goal should really be.

As for the symbiotes themselves, being less independent and smart is a big downside on the side of bees. They're a lot less cunning and skilled about getting hosts.

I really like these cuddlebugs, and how they bring on the thiccness to their hosts.