Star Wars isn't my nom but I'll take a crack at it.
Those are indeed all Legends characters. I'm not sure why you want to rename/subdivide it. Is it because of the "All Media Types" tag? Star Wars Legends mainly consists of novels but there are enough comic books (and maybe other media, I can't recall) that the canonical tag is AMT. You could perhaps make a Star Wars Legends novels tag if AMT is the issue?
If the issue is that the tag is too broad, then I am pretty sure these characters would all fit under "Star Wars Legends: New Republic Era - All Media Types". However, it depends when the original nominator intended to request them, as most of the characters live beyond the end of the New Republic.
As for splitting... if you go by where the characters first appeared (I've listed them below), it would be possible to split the characters into "Star Wars Legends: X-wing Series - Aaron Allston & Michael Stackpole" and "Star Wars Legends: Thrawn Trilogy - Timothy Zahn". However, there's a lot of crossover between the Legends sub-series and all of these characters appear in other series. (Corran Horn & Tycho Celchu both appear in Thrawn Trilogy, etc.)
Corran Horn - first appearance Missed Chance (prequel to X-Wing: Rogue Squadron) Jaina Solo - first appearance The Last Command (Thrawn Trilogy #3) Mara Jade - first appearance Heir to the Empire (Thrawn Trilogy #1) Thrawn | Mitth'raw'nuruodo - first appearance Heir to the Empire (Thrawn Trilogy #1) Tycho Celchu - first appearance Star Wars: X-Wing Rogue Squadron: The Rebel Opposition Ysanne Isard - first appearance X-Wing: Rogue Squadron
no subject
Those are indeed all Legends characters. I'm not sure why you want to rename/subdivide it. Is it because of the "All Media Types" tag? Star Wars Legends mainly consists of novels but there are enough comic books (and maybe other media, I can't recall) that the canonical tag is AMT. You could perhaps make a Star Wars Legends novels tag if AMT is the issue?
If the issue is that the tag is too broad, then I am pretty sure these characters would all fit under "Star Wars Legends: New Republic Era - All Media Types". However, it depends when the original nominator intended to request them, as most of the characters live beyond the end of the New Republic.
As for splitting... if you go by where the characters first appeared (I've listed them below), it would be possible to split the characters into "Star Wars Legends: X-wing Series - Aaron Allston & Michael Stackpole" and "Star Wars Legends: Thrawn Trilogy - Timothy Zahn". However, there's a lot of crossover between the Legends sub-series and all of these characters appear in other series. (Corran Horn & Tycho Celchu both appear in Thrawn Trilogy, etc.)
Corran Horn - first appearance Missed Chance (prequel to X-Wing: Rogue Squadron)
Jaina Solo - first appearance The Last Command (Thrawn Trilogy #3)
Mara Jade - first appearance Heir to the Empire (Thrawn Trilogy #1)
Thrawn | Mitth'raw'nuruodo - first appearance Heir to the Empire (Thrawn Trilogy #1)
Tycho Celchu - first appearance Star Wars: X-Wing Rogue Squadron: The Rebel Opposition
Ysanne Isard - first appearance X-Wing: Rogue Squadron