I put a lens from an old Logitech logi camera in one of my v3’s, the field of view is slightly wider (1 degree) and has slightly better color reproduction than the default v3. Focusing it was a pain though.
Different lenses can make the view round or distorted (fish-eye) or upside down and backwards, most do not have the correct focal length to focus onto the sensor correctly (won’t focus no matter how close or far).
At some point I might try using a lens from my broken battery pro cam (or an og cam lens, as I’m about to take a sledge hammer to that one for never connecting) in a v3.
And as always, modifications to the internal lens will void warranty, its not recommended for most.