Based on the Replica set and the amount of Alphas.
Divide 12 per 3 = 4 Groups.
The data is replicated per group.
Group 1
name.user (replicated 3 times within the group)
age.user (replicated 3 times within the group)
Group 2
name.product (replicated 3 times within the group)
value.product (replicated 3 times within the group)
track.product (replicated 3 times within the group)
Group 3
ticket.transaction (replicated 3 times within the group)
status.transaction (replicated 3 times within the group)
3 Alphas serves the same data within the Group. I personally recommend that you separate each Alpha of a Group in a separated host. This way you avoid for example crashing a K8s node with Alphas of the same group.
If you have replica set as default, you gonna have 12 groups.