To change the OS user name (file/group ownership for AE) is not as involved as changing the DB user name.
If the user/group is local to the system, then it's just a matter of changing the file/group ownership of the AE install path recursively (services need to be stopped before changing ownership). If the user is external (LDAP, Active Directory, etc), then ensure relevant 32bit libraries (SSSD, Samba winbind, etc) are installed so that AE is able to lookup the user name correctly.
As for the DB user "autosys" (default) change, although it is doable, it is NOT recommended. One of the reasons being, any changes post installation is not fed back to the installer registry which is used for future upgrade/maintenance. The installer might expect/assume the default "autosys" DB user from the original install during upgrade or repair or patching. Even for audit purposes, one might have to audit multiple users as opposed to autosys user across the board.
If you still choose to do this, then the following steps :
1. Ideally, your DBA should clone/copy the "autosys" DB user as the new/replacement user (e.g; autoprd)
This might help: Duplicate an Oracle database user - Database Administrators Stack Exchange
2. Grant the UJOADMIN role to the replacement user, for example: autoprd. It is part of the UJOADMIN role privilege reintroduction: https://docops.ca.com/ca-workload-automation-ae/11-4-2/en/installing/ae-installation/reintroduce-the-ujoadmin-role-privi…
3. Update the DBAccess attribute of the $AUTOUSER/config.$AUTOSERV file with the replacement user and password:
DBAccess - CA Workload Automation AE & Workload Control Center - CA Technologies Documentation
4. If you are using Oracle PKI Authentication, then additional steps need to be done:
https://docops.ca.com/ca-workload-automation-ae/11-4-2/en/installing/ae-installation/environment-and-database-connection…
I hope this helps!
Best,
Chandru