There are a few rumours now crossing each other, lets be very careful with this.
Firstly, Disneyland is rumoured to see how they can make Galaxy's Edge more integrated with hot IP's like Mandalorian. As they currently don't fit in the timeline of the land.
Second, the French Government and Disney have indeed an agreement for additional Parks being build with the land they purchased in the 80's, This has nothing to do with the extension of Walt Disney Studios Park. This extension is just a fix Disney is doing and not with the agreement to build a third park by 2037.
The Lion King Rumour has gone around for the last 10-15 years and never made footfall into the Paris resort, Splash Mountain was rumoured as extension for the back of Frontierland. Plans have been prepared for this, drawings are available on the exact position of it but so far Paris has not gone any further.
Star Wars will come in a form or shape into the parks, with an immersive land as this IP is hot and has been for the last 20/30 years in Disney parks around the globe. So far no permits have been filed for the construction of Star Wars Galaxy's Edge, only for the Frozen expansion, so it will be a waiting game when we can see this coming as the land should open in 2024. Which will give Imagineering enough time to future proof this land with potential new Star Wars IP's integrated.