I use a plugin such as nginx in ansible playbook.
https://galaxy.ansible.com/nginxinc/nginx_core
On server I can use cli to install the roles and collections as
ansible-galaxy collection install nginxinc.nginx_core
But how can I install it on AWX(Tower)?
I tried to run the command in one of AWX container - awx-ee (others are awx-web, awx-task, redis). When run a template in AWX, it still caused a role not found error.
In addition to @Zeitounator comment, you could also manually install your collection into a dedicated path (i.e into collections folder from awx directory)
If you use a requirements.yml file :
sudo -u awx_user ansible-galaxy collection install -r /var/lib/awx/projects/my_project/collections/requirements.yml -p /var/lib/awx/projects/my_project/collections
or manually
ansible-galaxy collection install ansible.my_collection -f
'/home/.ansible/collections/ansible_collections/ansible/my_collection'