Are these legal

dust caps for car / motorcycle with flashing led green light as wheel turns legal or not ■■

Don’t see why not… just implies ‘look at me!’ imo.

No they are not legal flashing lights unless indicators cannot be used,

Silverback
3 Feathers Haulage

Like all fancy bits / parts for motors, to be legal im pretty sure it has to be ‘E’ marked and approved and other such parts are deemed as “show use only”, like those stupid sqiggle font number plates are.
I wouldn’t worry to much though, its hardly life threatening and at worst you’d probably just be asked to take them off and be on your way.