How to use reverse DNS with own Domains

[fmt-Println-MKO]

I also use Hetzner DNS for my Domains,
at the moment, after the cluster is created, I need to make the DNS (IP) changes by myself.
Or after I deploy a web app, I also need to make the DNS changes.

how can I integrate this

1. into cluster creation, for Rancher, or just the reverse DNS for all the servers?
2. for my own app deployment, after deployment, DNS is connected to the new LB?