How do I force an item to move to another creative tab?

I created my own custom item, and since, well, I'm a proger, I decided to add it myself, which is why I now have a locked code element that is not in the creative tab that I need.
I've tried to rewrite creative tab by force and create my own, but it doesn't help. MCreator itself does not allow updating system files - it overwrites them during the build. I don't want to leave it, it's a very convenient collector and organizer for mods.

My item

Creative Tabs