Love? Interesting question. I would think that most of them have a sense of well being for their creations or whatever their domain is. Romantic love is harder to place. I once defined that everything not fitting within the definitions of mortal life by Xerneas and Yveltal does not have the need to reproduce. While romantic love is indeed a separate emotion from this, I still feel they are connected. That is not to say that they don't know what romantic love is, as the vast scope of their power would demand such knowledge. While they may or may not be able to feel it themselves, I imagine they can feel it through others that can. Although I guess that would still count as them knowing fully what power the emotion has. Otherwise, through the power of the lake trio, I also defined that all legends have basic sentience, so this is also a way in which one can say they know love. Can they fall in love with each other or lesser pokemon? Depends. For the pokemon that were made or can be said to be made by other legends, I imagine they see those as parental or authority figures, and such a thing is out of the question. Same level might be possible, but such a thing may cause difficulty in workplace relations. (the world may go out of wack as a result) Lesser may or may not be possible. I can see it maybe, but again, problems with workplace relations. If it's with more ordinary pokemon, then I can only see that being possible with junk like the lowest tier of legends since they're not that far removed from ordinary pokes anyway. All else may not even consider such a thing since they get increasingly insignificant to them.
