Actually, I have got the Genesect drives myself in a hacked raid, and they have a description (in my language, which is French). Also, they don't seem to behave badly (not a question mark item) so... I believe you'll get them like how we got Ash's Cap? Show the Genesect to some guy and he gives you the drives?
every item is "in" the game but they aren't
in the game. They have their image, they have their description, but they won't actually do anything since the effects aren't actually inserted.
Its similar to Pokemon in that regard. The snapped pokemon are still "in" the game, they have their base stats and gen 7 levle up move pools and such, but they obviously aren't like...in the game, ready to go. Likewise, the fact the Crown Tundra additions were removed from certain listings is how we know they're clearing the run way to get added properly.
That said yeah most likely you will just take Genesect to the guy and you'll get whatever, either the drives (now properly implemented since the IoA datamine) or a new item.