hmm OK I see what you are saying. I wonder if exceptions in the code can be made for this card to be targetable by Butterfly Effect?
If not, then the only similar idea I currently can think of is that if Butterfly Effect is used on the field at all, then Psy Butterfly would duplicate. I think this might not be too UP, because although this means adding another card for the combo to work, it also means that a single Butterfly Effect could produce multiple Psy Butterflies depending on how many there were on the field to begin with.