I'm voting DO NOT BAN for both.
* Mega-Sableye: My judgment doesn't change since yesterday.
* Deoxys-A:The suspect of a God is very different that a suspect of a receiver . In this suspect we judge Deoxys-A's teams and not the pokemon himself.
Let's explain the schema of a Deoxys-A team.
* ATTACK : Smeargle | Dugtrio | Marowak-Alola | Mimikyu | Araquanid | Pikachu |
* SPECIAL ATTACK : Swellow | Tapu Lele | Serperior | Tapu Koko | Araquanid |
* SPEED : Heracross-Mega | Marowak-Alola |
This isn't a restrictive list. So, this kind of team has 3 powerful sweeper who make a lot of damage to any pokemon without gift.
And for the other pokemons, we have the choice: hazard removal, spiker, trapper, sweeper, revenge killer :
* HP: Shuckle | Skarmory | Dugtrio |
* DEFENSE : Hoopa | Ditto | Nihilego | Pyukumuku
* SPECIAL DEFENSE : Kartana | Ditto | Pyukumuku
The Deoxys-A teams are classic.
When I saw the rules of this metagame, I was afraid of the power of HO Deoxys teams. But when I played against this type of team, I won because I could stall these.
I don't think like you Pipotchi, I think that M-Sableye teams destroy Deoxys-A teams. When the battle is a opposition Stall/Offense; the key of the victory is hazard control. And M-Sableye is a GOD in this issue. [ It's not the argument we need broken to counter broken because I think that Sableye doesn't deserve to be ban. ]
And if we play Shuckle teams ( It's a team with Shuckle as God ), we have 2 SUPER-Staller with respectly 614 of SPE Def and Def and we can Hardstall HO easily.
Deoxys-A is the most common pokemon in this tier and the most common God. But I consider that he doesn't deserve the ban.
That's just my opinion.
ps: Don't forget that SMOGON hates complex ban, so if you consider that (HP) M-Sableye is broken, so (Speed) M-Sableye will also be banshed.