This is useful if you want to register other function names as console commands, besides the functions names with the prefix.
In the example image show the function IncreaseSpeed will be available as a console command.
Multiple instances - Register for this Actor Instance
This is useful if you want to execute the console command on a single instance of an actor in the case there are multiple instances.
If it is checked the owner actor instance will have registered console commands using the following format <FunctionName>_<ActorNameRuntime>
where for example <FunctionName> is Cmd_PrintTest and <ActorNameRuntime> is generated at runtime once you play the level.
When not to use
For the example presented in the simple case where we only have oneFirstPersonCharacter in the level it is not that useful, because the general command
will be the same as the instance command.
A proper use for multiple instances would be a projectile, like the FirstPersonProjectile