As of this post (December 20th, 2019) we do no yet have support for the USCutter line of plotters, and for the Roland VersaCAMM cutters such as the Roland sp300v (though non-VersaCAMM plotters may work fine.) EagleCut is a beta product, and as such we are always adding support for more plotters.
We plan on having support for both sets of plotters in February. Meanwhile, drop us a quick email and tell us you want to know when support for your plotter is available!