Is it able to bypass account verification on development environment for joining multiplayer game?

[Dayo]

When I was on lower version of MC, its free to join multiplayer MC server so I usually debug launching multiple instance of minecraft client on one laptop and execute server instance in there too(for easily investigate exception logs)

From some days, it doesn't works now because of multiplayer disabled.

I found this article about making authorization of development env in other post but it seems to fix username by my account.

https://gist.github.com/50ap5ud5/beebcf056cbdd3c922cc8993689428f4#minecraft-authentication-in-dev-environments

 

I want to change my username and multiple instance has not duplicated UUID. Is there any method available without purchasing multiple Minecraft as I want?

Using MultiMC or third party launcher which provides offline launch support works fine but to do that, it requires unnecessary steps belong executing with IntellIJ directly