By default you can’t replicate a TMap.
Method 1
By using a struct that warps your TMap you can replicate a whole TMap.
Here is a code snippet of the NetSerialize function body you must implement in the struct. (This method sends the whole array, NO DELTA detection)
Thanks to Jambax (UE Source Discord)
Method 2
For a large TMap, another method is to have use a fast array.
Each entry of a FA struct holds a Key and its Value.
Using the events of the FA you can reproduce the TMap locally.