This works, but they're not split up, each of them get the same amount. So, for example:
You're using a Huntail to fight a wild Zangoose for 2 Attack EPs, and you have a Roselia that's holding the Exp. Share. Both your Huntail and Roselia will each get 2 Attack EPs.
If your Huntail is holding a Macho Brace, both of you get 4 Attack EPs each.
With PokéRus and Macho Brace, you'd get 8 Attack EPs each, but both Pokémon would need to have the PokéRus for them each to get 8. If just Roselia had the PokéRus, then only she would get 8 Attack EPs, while Huntail would only get 4, and vice-versa.
...Of course, who'd want to EV train a Huntail's Attack stat?![]()