“I was told that AP scores can basically fill in for the SAT subject tests.”
Who told you that and in terms of what? Per the UVA Admissions webpages, it is stated that 2 SAT subject tests are “strongly recommended” in one spot, and “strongly urged” on another page. Whenever we saw wording like that, we always interpreted that to mean it could hurt the application if we didn’t do whatever was “strongly recommended”. Not necessarily that it was mandatory, but doing whatever was recommended would serve to help our chances. IMO, since you are OOS, and sound like you don’t have any special “hooks”, I’d make sure you are doing everything you can to make your application as strong as possible. UVA does not require you to submit all test scores for all standardized tests taken. (They do actually encourage you to, since they will superscore). So, if you end up doing poorly on the SAT2’s, and think it will hurt your application, you do not have to send them those scores. You have nothing to lose by taking them. Plus, some other schools you may be considering may actually require them or “strongly recommend” them too.