If you're familiar with Godot already then I'd say it's very feasible and you will have fun! The most important thing is to do some planning before the jam starts. For example, do some game design, planning out your main mechanic and deciding how will you put your own spin on the genre. Decide what assets you might use (color palette, sprites, sounds etc.). I just found this tutorial for Godot peeps. Definitely check that out (or others that may be around) and try to make it through before the 7drl. It will give you some experience on how to organize your code and offer a chance to come up with unique ideas for the jam.