Only George Mason has Air Force ROTC (and even it is sponsored by the University of Maryland, where most of the military classes would be held). Naval ROTC is only at ODU and also offers a Marine Corps track which you might like. Army does appear to have somewhat lower academic standards, otherwise it is not easier.
Both the Navy and Army definitely offer two-year scholarships. I assume these are available to transfer students (they used to be). The Air Force might not have two year scholarships anymore, but don’t assume it… ask them personally (see below).
http://www.nrotc.navy.mil/scholarships.aspx
http://www.goarmy.com/rotc/college-students/two-year-scholarships.html
However, you need to pay attention to any deadlines. I recommend that you email the ROTC departments at each of those colleges. Ask them what you need to do to enter their programs. They are the experts. You might even want to visit them in person.
https://www.odu.edu/nrotc