Hi!

For our Roleplay server, this would be useful for character creation, private RP events and separate dungeon groups.

Players in different instances should not see, hear or interact with each other. NPCs, world items, combat and spatial voice should respect the same separation.

For example.:
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local instanceId = createInstance()

setPlayerInstance(playerId, instanceId)
setNpcInstance(npcId, instanceId)

-- Return to the main world
setPlayerInstance(playerId, 0)

-- Once players have left
destroyInstance(instanceId)

__________________________________________

Server-controlled membership and clear cleanup rules would help prevent entities or interactions leaking between instances.

I couldn't find this in the wiki. Is something similar already available or planned?

Your idea is similar, which was discussed here:
https://g1r-mp.com/forum/showthread.php?tid=21