We started our game back before mechs were trendy again.
We were granted a non-commercial license from Microsoft back when nobody was doing anything with their IP, so Microsoft saw no harm in letting us use the content, with the firm obligation to never make a buck. Nowadays, if you tried this shit, you'd be stomped out of existence and not granted a license simply due to the fact that Piranha has a full, exclusive, digital distribution license of the MW franchise for X years.
We're having a hard enough time staying under the radar and out of the firing line, and we were here first, AND we have an actual non-commercial license from Microsoft themselves.
You're better off creating your own IP. We've learned this the hard way.