Fable team have 2 quest designer, 5 level designer, 1 gameplay designer, 1 technical designer, 5 Game designer & 1 Creative director that's 15 designer.
Avowed Team have already a big team of at least +12/13 Area Designer (Mix of Level designer, Technical designer & Quest designer) not to mention their combat designer team, Systems designer, narrative designer, it already goes up to roughly 30 designer (and they still recruiting)
For reference :
The Witcher 3 is 45 Designer team (including writers)
Cyberpunk is 90 designer team (including writers)
HZD is 39 designer team (including writers)
Fallout 4/76 is 33 designer team (including writers)