M-OUSE currently West of Paris at angels 39 headed SSE.
Highly likely to be C-130J tankers of the 128th Refueling Wing out of Milwaukee. There were war games planed in Las Vegas at Nellis AFB but they were cancelled due to some people being positive for Coronavirus.
Airbus Voyager tankers were also seen to be headed to Nellis recently.
Military planes tens not to have transponders and they only turn them on when they want to be seen.
Ultralights usually only fly under visual Flight Rules, i.e. in daylight.