Different villians: sith purebloods, the story of the ST is the OT cast confronting the darkest hour of the republics past and wrestle with the subject of genocide and reparations, as the republic ordered a sith holocaust in the past. The sith pureblood faction is called “The Sith’ari Dominion”
Different heroes: a sith pureblood defector turned Jedi, a princess and senator from the Hapes consortium trying to politically manipulate stuff behind the scenes to avoid further bloodshed, and a mandalorian Jedi trained by Luke Skywalker who will develop an LGBT relationship with the sith pureblood defector and train him in the ways of the force…an enemies to partners, partners to friends, friends to lovers story.
Different story: the mandalorian hegemony is secretly provoking war between the republic and the sith’ari dominion in order to sell weapons to both sides, the use of WMDs weakens both factions as the Hegemony plans to invade and conquer both weakened factions with our heroes forced to stop the war before it is too late.
Different republic: the free planets alliance was in a generations long war Against The Fel imperium, eventually leading to a merger of the factions called the United republic after the Moff Council betrayed the fel fynasty, the United republic is at war with the Sith’ari Dominion