Currently, end gateways on the main island are broken and do usually take you back to the obsidian platform (see
MC-138069). There is however a workaround, see this comment.
Now that we have a working end gateway, we can actually use it to get to the outer end islands ... or can we?
While we now have an end gateway which nbt data is consistent with one of 1.13.2, it does take you to a tiny island, merely generated for the gateway portal itself, still far away from the outer end islands
- Go to the end (/setblock ~ ~ ~ minecraft:end_portal)
- Kill the ender dragon (/kill @e[type=ender_dragon])
- Go to the generated end gateway and replace it with one that actually works (/setblock <pos> minecraft:end_gateway destroy)
- Use an ender pearl to get through it
→ You are on a tiny island far away from the outer end islands
As LapisDemon pointed out, it seems to be the case, that the outer end islands generate much further away than in previous versions. Whether or not this change was made intentionally, it seems to be the case that the end gateway's distance was not updated accordingly. Since the game cannot find any blocks where it wants to generate the gateway, it generates a tiny end island to at least have some place to put the player.