I want my game to be similar to an arcade game that I've already clicked on as a mini-game played in a 2D UI. Is this possible and is it interesting?

Decentraland is a 3D environment, so you'd need to consider how 2D would work in this space. Take a look at some of these example open source scenes for inspiration https://studios.decentraland.org/resources

But by all means, if you'd like to make 3d arcade machines that open a 2D UI, great!