I've got an interesting problem, when i use the portal sign method, World Inventories doesn't graphically update the switch in inventories, however if i use the /mv tp everything works perfectly, the World Inventorie plugin dev says it might have something to do with the "inventory changed" event.

Heres the link to the bug report and him/her's response : https://github.com/Drayshak/WorldInventories/issues/9#issuecomment-2727717

I find this interesting on a couple levels, since (AFAIK) Multiverse doesn't touch inventories, and MultiInv doesn't have this problem.

In any event, can you provide some more info, including your CB version, build numbers of all your Multiverse plugins (actual numbers, not "latest"), and concrete steps to reproduce?

Its pretty simple to replicate on my server at least, link the worlds via signs punch the sign to take you to the world pick up a block and then go back to the world in which you came you should have a ghost item if you move the item or reconnect it'll instantly disappear, displaying your correct inventory, if you go back to the same world where you got the block it wont show you your items until you reconnect or force it to do something with your inventory, mainly seems to come back if you just move stuff around. If you use the /mv tp command inventories update perfectly. Sometimes it will show afew of your items in your action bar so its best to fill everything up to see it happen. Also I was thinking about it today and could it be a spout bug? I know spout claims to have alot of inventory monitoring features, this bug appears in both spoutcraft and vanilla mc.

World Inventories v0.0.12

13:56:00 [INFO] [Multiverse-Core] Multiverse-Core Version: 2.2-b329
13:56:00 [INFO] [Multiverse-Core] Bukkit Version: git-Bukkit-0.0.0-1131-g86b7fa8-b1344jnks (MC: 1.8.1)
13:56:00 [INFO] [Multiverse-Core] Loaded Worlds: 6
13:56:00 [INFO] [Multiverse-Core] Multiverse Plugins Loaded: 3
13:56:00 [INFO] [Multiverse-Core] Economy being used: iConomy 6
13:56:00 [INFO] [Multiverse-Core] Permissions Plugin: Bukkit Permissions (SuperPerms)
13:56:00 [INFO] [Multiverse-Core] Dumping Config Values: (version NOT SET)
13:56:00 [INFO] [Multiverse-Core] messagecooldown: Not yet IMPLEMENTED
13:56:00 [INFO] [Multiverse-Core] teleportcooldown: Not yet IMPLEMENTED
13:56:00 [INFO] [Multiverse-Core] worldnameprefix: false
13:56:00 [INFO] [Multiverse-Core] enforceaccess: false
13:56:00 [INFO] [Multiverse-Core] enforcegamemodes: true
13:56:00 [INFO] [Multiverse-Core] bedrespawn: true
13:56:00 [INFO] [Multiverse-Core] debug: 0
13:56:00 [INFO] [Multiverse-Core] Special Code: FRN002
13:56:00 [INFO] [Multiverse-SignPortals] Multiverse-SignPortals Version: 2.2-b130
13:56:00 [INFO] [Multiverse-Portals] Multiverse-Portals Version: 2.2-b296
13:56:00 [INFO] [Multiverse-Portals] Bukkit Version: git-Bukkit-0.0.0-1131-g86b7fa8-b1344jnks (MC: 1.8.1)
13:56:00 [INFO] [Multiverse-Portals] Loaded Portals: 0
13:56:00 [INFO] [Multiverse-Portals] Dumping Portal Values: (version NOT SET)
13:56:00 [INFO] [Multiverse-Portals] wand: NOT SET
13:56:00 [INFO] [Multiverse-Portals] useonmove: NOT SET
13:56:00 [INFO] [Multiverse-Portals] enforceportalaccess: NOT SET
13:56:00 [INFO] [Multiverse-Portals] portalsdefaulttonether: NOT SET
13:56:00 [INFO] [Multiverse-Portals] portalcooldown: NOT SET
13:56:00 [INFO] [Multiverse-Portals] Special Code: FRN001
13:56:00 [INFO] [MultiVerse-NetherPortals] Multiverse-NetherPortals Version: 2.2-b284
13:56:00 [INFO] [MultiVerse-NetherPortals] Bukkit Version: git-Bukkit-0.0.0-1131-g86b7fa8-b1344jnks (MC: 1.8.1)
13:56:00 [INFO] [MultiVerse-NetherPortals] World links: {}
13:56:00 [INFO] [MultiVerse-NetherPortals] Nether Prefix:
13:56:00 [INFO] [MultiVerse-NetherPortals] Nether Suffix: _nether
13:56:00 [INFO] [MultiVerse-NetherPortals] Special Code: FRN001

I had a similar issue with a Give-plugin + TMI since... Minecraft 1.6, I'd guess. It was exactly as you said: I gave myself an item but I just couldn't see it. When I changed anything in my inventory the items suddenly appeared. The bug is now gone with the 1.9 pre-release. But first you should make sure that it's not a client-side bug maybe even caused by a mod.

So I'd recommend you to try it with a fresh minecraft.jar and see if the issue persists.

No confirmation or update since November 15; closing issue.