I’ve put online my rough partial draft of the theory of bijective correspondence between frames/locales and certain pointfree funcoids.
Pointfree funcoids are a massive generalization of locales and frames: They not only don’t require the lattice of filters to be boolean but these can be even not lattices of filters at all but just arbitrary posets.
Much work is yet needed to relate different properties of frames and locales with corresponding properties of pointfree funcoids.