The Seed of the Sacred Fig (Iran->Germany) & Santosh (India->UK). Could (should?) have had All We Imagine As Light from France instead of India.
While these may be due to political reasons (& therefore a positive), in future its possible a country tries to get multiple movies nominated by having co-produced movies nominated via another country. Wouldn't put it past China to try to get some in via SE Asia (given that's how they circumvent trade barriers). Russia could have a movie made in friendly countries like China/India/Iran & try to get a nomination (state sponsored ie as opposed to movies showing the reality which would need to go via other countries due to a ban in Russia). Ultimately has to be well made to even reach a top 5 nomination stage (a few recent years for me - the international film nominees have been better movies on avg than the Best Film nominees & there've been good ones left out), so such movies may not have a chance but still, this is a loophole that could lead to controversy in future esp as the main language of the film is most such cases may not be native to the country from which it's getting nominated.
Might as well solve the problem by nominating best 15/5 films without putting a country name next to it (reducing the associated jingoism) & also allowing for multiple noms from 1 country if they're good enough.