My suggestion is to add a way to execut silent commands (without the message in-chat to the target)
For example, the /eco [give/take] command have that annoying message (i know it can be removed from messages_##.properties but maybe you don't want to remove it at all).

/eco take GabyTM 1234 -s

Do you want to prevent players being informed when you do /eco commands? The only way to do this currently is to remove the messages from the locale.

I'll mark this as an enhancement - perhaps we could add a sendMessage method to EssentialsCommand that doesn't do anything if the command is silenced. Though, I don't know what syntax could be used that isn't ambiguous.

Closing this for now, but leaving as open to PR in case someone is actually interested in trying to implement this.