How to share gitlab KAS between projects

I deployed KAS agent and connected gitlab to my k8s cluster. connection is success.
agent is connected at project group-a/project-a

I dont want to connect it for each and every projects. how do I share the agent to another project lets say group-b/project-b

this is the below attached sample. while creating env in group-a/project-a im able to view the agent while creating environment but when I do the same in group-b/project-b im unable to do so

this is the config.yml I placed in group-a/project-a master branch under .gitlab/agents/kaer-morhen/config.yaml

user_access:
  access_as:
    agent: {}
  projects:
    - id: group-a/project-a
    - id: group-b/project-b

ci_access:
  groups:
    - id: group-b
    - id: group-a

how do I share the agent between group project. is it possible in first place. I see many documents related to sharing project but none of them seems to working for my use case.

the purpose of this is I could use the agent in ci environment