In Candlepin, content overrides are attached to a consumer (content host) and have 'name' and a 'value' attributes:

hammer activation-key content-override [OPTIONS]

--override-name VALUE Override parameter key or name.
To enable or disable a repo select 'enabled'.
Default value: enabled
Default: "enabled"
--value VALUE Override value. Note for repo enablement you can use a boolean value

In the web UI, the only content overrides displayed are those with the name 'enabled.' However, you can use subscription-manager to set other overrides on the host. For example:

subscription-manager repo-override --add gpgcheck:0 --repo satellite-client-6-for-rhel-8-x86_64-rpms

This will cause your redhat.repo file to be altered to say

gpgcheck = 0

In Katello, we do not support or display any overrides besides 'enabled'. However, they can be added via hammer. As these are unsupported, we should disallow this in Hammer as well.

needs removal from both

hammer host subscription content-override
hammer activation-key content-override