It's easy, you just have to think and reuse existing code.
Okay, then..
- open any command, can be Escape
- copy the code, create new file paste it
- remove the destroy, teleport, checks and/or whatever part you think is useless
- search for "settitle" command
- copy the code, mainly the line player.setTitleColor obviously, no need further explanations what's that and other broadcast lines, hello, if those lines are there, you need them as well
- I see errors on parse something, well, replace it with static code
- but how? Search for gm color config, see how is builded the line and do the same
- register the handler, usercommandhandler
- enjoy
Got errors? Post em here, show that you are trying and you are willing to learn. Otherwise don't bother opening a server, even a local one. Sad but true.
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You said you tried, show me the code.