I’ve noticed that Apple does a pretty good job of detecting when I switch between English and Spanish typing on my Mac. On my phone/iPad it tends to defer to the keyboard (I have a default English/Spanish keyboard I use the most, but I have a few others that I use less often, most notably French, which I seem to occasionally switch to without noticing and then get weird autocorrects of my writing into nearish French words. Not as bad as some of the odd texts I’ll get from my ex-wife when she dictates something in English while her phone is expecting Spanish though.