How to organize inverters?

Question

Ansible

Hello
There is roughly the following host structure

[appA_domainX]
appA[1:2].domainX
[appB_domainX]
appB[1:8].domainX
[appC_domainX]
appC[1:9].domainX
[appA_domainY]
appA[1:2].domainY
[appB_domainY]
appB[1:6].domainY

There are the following launch algorithms to
roll out a playuk on half of the nodes, one / all domains from each group
roll out a playuk on for appA and B for both domains, one / two / three nodes from each group
roll out a playuk on for appB and C for one domain one / two/three nodes from each group
What is the practice of organizing an inventory or running a playbook in such cases?
I don't want to litter the inventory with all possible options duplicating hosts
It's not entirely clear if you use the
hosts: all
serial: 1 parameter
, will it just roll over 1 random host or 1 in each group?