The oracle-epel-release-el8 rpm should be updated to provide 'epel-release' (if indeed it is a full EPEL replacement), as other packages may require epel-release to be installed.
An example is the remi-release-8 rpm, which will not install without 'epel-release':
error: Failed dependencies:
epel-release = 8 is needed by remi-release-8.5-3.el8.remi.noarch
While it is possible to override this when trying to install the packages, the oracle epel package should provide this so it doesn't need to be forced.