Pandemic Legacy Researcher relationship (Feb spoliers)
This is one way only.

Reason:

Researcher ability works one way only (He can only GIVE card with his ability, NOT TAKE.)
Co-worker relationship make good combo with researcher, but don't extend his ability to the "taking" part. (Although, it is possible for other players, to take cards form researcher, in their turns. So also his co-worker can take advantage of this.)