From my understanding from the below questions which were asked quite some time back, Redis doesn't have a built-in support for master-master replication.
The official website as of now looks like there is nothing much to it about master-master replication. Is this still the case, i.e., does Redis still have no options for multi-master replication. And even third-party tools don't seem to be helping Redis achieve the same. I came accross Zabcluster and Zookeeper but I'm not sure if this would meet my requirement of a simple master-master setup without much additional complex changes.
Your research is accurate - at the moment, Redis does not provide multi-master.