I've noticed that Arcane trickster doesn't actually start with Mage hand in any way, and the suggested spells it offers when I pick Astarion as an Arcane Trickster does not even recommend Mage hand, nor does when finalizing the class choices does it offer it. This seems like a bug of some sorts especially since a large portion of the features of Arcane Trickster REQUIRES access to mage hand to use properly, and even says in the Player's Handbook for 5e that you learn 3 cantrips, one of which MUST be Mage hand.