Workflow_dispatch approach in gitlab ci

I have the following forked github repository, which uses the workflow_dispatch mechanism to differ the variables hostname and environment in every run.

I recognized that gitlab analyzed this behaviour already here. Further I was able to apply this but it seems it only affects the manual job and cannot be used for global variables. Also after running the job ones I cannot access the view to change the variables anymore.

Is it somehow possible to achieve something similar as it is possible with the inputs of workflow_dispatch?

We are on a self-managed version 15.1.2.