Legion is my favorite World of Warcraft expansion! Today, I'd like to show you how to stay on the Broken Isles during Shadowlands.
For lower level characters (10-50), you can just do a feature called "Chromie Time", which lets you level through any expansion you want, by talking to Chromie in Stormwind or Orgrimmar (depending on your faction). You can find Chromie by opening your map and looking for the small hourglass icon. When you talk to her, she'll give you a bunch of expansions to choose from. Selecting "the Legion Invasion" will let you level all the way from level 10 to level 50 in Legion.
To level a high level character (50-60) through Legion, wait for the Legion Timewalking event to come around. This makes it so you can do Legion dungeons and earn experience from them, no matter what level your character is. The only problem with this technique, though, is waiting for the event to happen, which may take many months. And, on top of that, it only lasts a week, when it is going on. Be sure to check the in-game calendar to see when the next one will be.
I hope that this guide helped! If you want to do stay in a different expansion, most of these strategies would work for all of them! Thanks for reading!