The Rise of Skywalker Teaser Trailer showed us that Palpatine will indeed return. JJ Abrams has gone on to confirm that he's back, in the flesh for real. George Lucas was brought on board for the project before they even wrote the script, according to JJ. In this old Star Wars book that was released when George Lucas was still the owner of Lucasfilm and Star Wars, before selling to Disney, it is revealed as to how Palpatine was going to return to take Anakin Solo...who I believe in this scenario could be Kylo Ren (taken after Jacen Solo). I believe Disney/Lucasfilm are combining ideas from legends and putting them all together.
What do you think??