I successfully paired with my phone and had to install pulseaudio-bluetooth to get a connection working, but now I can. Playing music on my phone while connected does result in my machine’s speakers being utilised. So the connection works.
But I am unable to transfer files either ways. So, upon inspecting daemon.log, I came across this bit:
Apr 25 22:24:13 localhost bluetoothd: Can't open input device: No such file or directory (2) Apr 25 22:24:13 localhost bluetoothd: AVRCP: failed to init uinput for ab:cd:ef:gh:ij:kl
And according to this section in the Gentoo wiki, this is due to a missing uinput kernel module. How do I fix this?