Sharp rotor of which rpm is aligned with VAWT, leading to no moving piece relative to another:
A single unity including a VAWT + a Sharp rotor + a VAWT + a Sharp rotor + a VAWT and so on, or a Sharp rotor + a VAWT + a Sharp rotor (and so on), is perhaps easier for managing than a stack of unities.
The Sharp rotors could be replaced with Flettner rotors (simple cylinders) that are rotated by the VAWT.