Zelda producer Eiji Aonuma revealed this information in an interview with IGN. When asked what games the younger staff on the Zelda team were playing, specifically what inspired them, Aonuma replied "[Something] I did hear that a lot of people were playing was Red Dead Redemption 2."
When asked what open worlds inspired the Zelda team as a whole, he said "When I was working on Breath of the Wild, the director [Hidemaro Fujibayashi] was playing Skyrim."
I remember Aonuma mentioned Skyrim and Far Cry as games he played while working on BOTW.