A couple of questions regarding Morrowind after leaving the empire:
1. Did they restore slavery? It seems the logical course of action since it was the empire who campaigned for abolition.
2. Are the Morag Tong still a legally sanctioned faction? I ask because in dragonborn we are sent to [spoiler]destroy a den of Morag tong assassins[spoiler/] and the chancellor refers to them as "fetchers". Also none of the assassins sent after the chancellor carry a writ of execution, which leads me to believe the are no longer a legal group (which saddens me because they were my favourite faction in Morrowind)

I imagine the Dunmer aren't quite in a position to restore slavery just yet and whether they do may depend on just how much influence House Dres has and also whether Sadras is pro-slavery or not. I don't recall House Redoran being too invested in slavery at least at the time of Morrowind.

Regarding the Morag Tong, a former member tells us they disbanded (Or should I say a former MoraNG Tong member ) so it's entirely possible that (if they are actually Morag Tong and not imposters) they wouldn't be a legally ordained organization under the new administration. That may change of course.

IMO they are fully funnctional and I'd even dare to say: semi-official

There's this Writ of Execution that mentions "official sancioned license " and "Honorable Playername" and there's that almost decade-long planning to get revenge "Served Cold" that is obviously sponsored by House Hlaalu, and couldn't be executed on spot, like in Morrowind.

Also, the former member says : "When the Red Mountain erupted in Morrowind, the Tong fled... spread to the nine winds. We made a pact that one day, we might reunite... but I believe that day is long in coming."

Fled and spread and made a pact to reunite. No word "disbanded".

Majority of them and their holds were smashed during the Fall but they still function semi-officially as they weren't disbanded per se.

also with the Dark Brotherhoods fall they will become official and powerful as they should, because these crazed lunatics of DB are nothing short of murderers, not assassins.

They are strong enough to stop hiding from DB and attack DB operatives in Solstheim. They will be good.

Yeah, I personally hope that in TESVI we get to choose between the DB and the MT. If that comes to pass I'm definitely going Tong

Turns out the law becomes ambiguous when your capitol of state is eviscerated by a comet and volcano.