A BxG Quick Transmigration ( with a system) with a female protagonist who is always thinking of destroying the world, but stops because of her lover. She can customise the system space where she rests and take some objects of her lover in the worlds she traveled to. Once, her lover was a soldier so she customised the space into militar green.
Waaah! I know this novel! I have read it before using MTL but I just forgot what the title was, and I even forgot whether this was translated but you can try to check my Rec List (whenever I see someone translated those raw novels with a quick transmigration theme I added it directly to my rec list)
I think it's this? Quick Transmigration: Report to the Host, You Have Been Attacked! (...not read it in a loooong time so I may have remembered wrongly.)