Yes he can because nobody challenged Obama when he relocated black Somali and African immigrants into Idaho, Montana, Minnesota, and other majority-white states who never asked for those immigrants.
Sanctuary cities are ASKING for more immigrants, so yes, Trump can give them what they want.
There is no doubt that illegal immigrants will destroy the prosperity of San Francisco and other sanctuary cities like they've done in their home countries, Like a plague, they will replace white Americans in all different jobs. Merely look at the surnames in the California Legislature and you can see that aliens and their children are taking over our government offices.
So dumping illegals into sanctuary cities is not a good thing, but it is a teaching moment for the Leftists who asked for it. Perhaps it is even justice?