I spent a fair amount of time researching this on the forum and even though I've seen people asking for this since 2014 it's sad to see this is not yet implemented.
More and more Motion Graphics/Videogame/Film artists, like myself, are moving into Fusion 360 (because it's a kickass program) but it's not really fair or productive to have to spend another $300 on a software like Moi just to export F360 Step files as OBJ with Quads.
I think having the option to export in Quads directly from Fusion 360 is a must have. I (for example) need to bring my models back into Cinema 4D for animation, texturing, rendering, and we all know that you can't really UV Map correctly with triangles. There's just too many reasons why this is needed, even huge artists like Kirill Chepizhko have made requests (in 2015) and still this is not implemented.
Please make this happen Autodesk.
PS: I know you can select a body and export to OBJ, but if you have 10+ bodies and you have to do this for each one separately, it becomes super time consuming. On the other hand I can export a Step File which carries all the bodies in my scene, bring to Moi and export as OBJ (quads) and I get all my bodies in quads in C4D. 5 clicks vs 50+ clicks.