ACLableSyncedObjectEnabled checking status for cross permissions of exchange 2016 and the cloud exchange

Office 365 moving from Exchange 2016 cu 16. Hybrid environment. moved three users. working fine having issue with full permissions, send as, and send on behalf.
I am one of the users that moved to office 365 for testing. gave myself full permission on one of the mailbox on the premises. I had to add it manually in the account settings, more settings, advanced, add. it took time to open and i can see everything in that mailbox in outlook.

I assume auto-mapping does not work in the environment even though everything on the internet says that it should.
3 days later , I added another mailbox full permission to my mailbox, add it in outlook, and i cannot open it to see that mailbox. the old one that i added works fine.

my issue how do i check what Microsoft documents talking about checking


"Set-OrganizationConfig -ACLableSyncedObjectEnabled $True"

it should be applied to Exchange 2013 and some documents says i need to apply it to Exchange 16 too.
Also, it needs to be applied before you move any mailbox, otherwise you have to set permissions manually.

my question how do i check ACLableSyncedObjectEnabled and other attributes related to delegation permissions between on the premises and the cloud organization.