So to elaborate on the solution, if you have a Replicated UObject you have created and need Blueprint Variables to also replicate add this to the root class of your replicated UObject’s GetLifetimeReplicatedPropers:
UBlueprintGeneratedClass * bpClass = Cast<UBlueprintGeneratedClass>(this->GetClass());
if (bpClass != nullptr)
{
bpClass->GetLifetimeBlueprintReplicationList(OutLifetimeProps);
}