The plans for Project Luminous, and they include a full exploration of the High Republic era that won't stand in the way of the Star Wars movies and TV shows currently in development. The story of Project Luminous will be told across multiple platforms, including comic book titles from multiple publishers, novels, and young adult fiction.
With the Skywalker Saga in the rear view mirror, Lucasfilm is looking to the future of the Star Wars franchise by building a new era to be explored. This new world is the High Republic, an era that will introduce fans to a new generation of heroes and villains. As of now, there are no plans for Project Luminous or the High Republic to have any impact at all on the Star Wars movies and TV shows, but if it succeeds, Lucasfilm could still make this the setting for a new trilogy or Disney+ series at some point in the future.
Considering that the High Republic is set before Jedi Knights policed the galaxy in their own way, making it easier for them to maintain the peace.
This isn't how things were during the days of the Old Republic, as depicted in video games like Star Wars: Knights of the Old Republic. Unfortunately for the people who lived in this period, peace was much harder to come by. The Old Republic era was plagued by wars with the Sith and other civilizations. It was these continuous conflicts that eventually brought the Old Republic to an end. The Jedi were stronger then than they were in the Galactic Republic era at least, but it would seem that they were at an even greater level of strength during the time of the High Republic.
They may or may not have something to do with the Sith. The Sith were a major problem for the Jedi in the Old Republic days, but it's hard to say where they fit into the High Republic - or if they fit into it all. Apparently, the characters featured in Project Luminous will have a new faction of villains to deal with: the Nihil.
In short, there are plenty of fundamental difference between the two periods, and enough to make them feel like two distinct eras, in case Lucasfilm ever does decide to incorporate both into their Star Wars TV and movie plans, but ittedly, the focus on the High Republic makes a Knights of the Old Republic film unlikely.
