In Unreal 5, you can temporarily change the logging verbosity for a category using the log command in the editor’s command line.

log <category> <verbosity>

e.g.

>>> log LogTemp verbose
Cmd: log LogTemp verbose
LogHAL: Log category LogTemp verbosity has been raised to Verbose.
LogTemp                                   Verbose  

If you wish to change it at startup, use the -LogCmds command line argument. You can specify multiple settings using a comma as a delimiter.

 -LogCmds="<category> <verbosity>, ..."  

e.g.

 -LogCmds="LogTemp Verbose"