This is more of a docker question than a selfhosted question, but i think that most of people here should be familiar with docker.

HA runs with network-mode : host (in order for autodiscovery to work) when my Nginx Proxy Manager is running on a bridge network (and in a different docker-compose.yml file), which makes them not see each other as far as I know. Could I maybe add an additional network to the HA like this:

networks:
  default:
    driver: host
  nginxnetwork:
     external: true