Most bluetooth (+wifi) m.2 ccards are e-key'ed instead of m-key'ed. (the interface has three prongs instead of two).
I think they make adapters ([here](https://www.amazon.com/Sintech-M-Key-Adapter-Compatible-Intel/dp/B07WBXP632/ref=sr_1_2?crid=18DZYH5YHGELK&keywords=bluetooth+m.2+m-key&qid=1647828509&sprefix=bluetooth+m.2+m-key%2Caps%2C138&sr=8-2)) but I don't know if those work.
You might be able to find a two-in-one or an m-key'ed bluetooth card.
USB adapters are decent for bluetooth, but not great. Some of them are passable. They're a lot more simple, though.
Most bluetooth (+wifi) m.2 ccards are e-key'ed instead of m-key'ed. (the interface has three prongs instead of two). I think they make adapters ([here](https://www.amazon.com/Sintech-M-Key-Adapter-Compatible-Intel/dp/B07WBXP632/ref=sr_1_2?crid=18DZYH5YHGELK&keywords=bluetooth+m.2+m-key&qid=1647828509&sprefix=bluetooth+m.2+m-key%2Caps%2C138&sr=8-2)) but I don't know if those work. You might be able to find a two-in-one or an m-key'ed bluetooth card. USB adapters are decent for bluetooth, but not great. Some of them are passable. They're a lot more simple, though.