A Friend in Need was intended to be a crossover when it was made, but since they never made a show featuring the Masked Rider who met the Power Rangers, there was never anything for it to crossover over with.
Err, yes, they did. Saban's Masked Rider
ran for a full season on FOX.
Power Rangers in Space
also did a crossover with Saban's Ninja Turtles: The Next Mutation
, though it's probably best to forget that.