Does 616 Hawkeye wear one or two hearing aids??
from 1984-1991, there are about 8 references total to clint having hearing aids. in some of those panels he just says "hearing aid," in others he says hearing aids (plural), but in any case he's shown to touch both the left and right ear at separate points.
a visual depiction of a hearing aid is only shown once (confusingly, the ear is not shown to be outside the mask so it doesn't make sense. let's attribute that to a coloring error despite the linework suggesting otherwise).
so, i would say after clint initially went deaf in hawkeye v1 #4, he wore in-the-ear (ITE) hearing aids in both ears (thus, two)
after clint is again deafened in hawkeye v4 #15 (2014), he's shown wearing behind-the-ear (BTE) hearing aids in both ears.
and then all-new hawkeye immediately switched that to ITE hearing aids
but, presumably, still in both ears. he switches back to BTE hearing aids in hawkeye v5, but it seems he only has one in the right ear.
he then was consistently portrayed with a BTE hearing aid in only the right ear
as for his last most substantive series appearances: in black widow & hawkeye, he wasn't really visually portrayed with any hearing aids, but a small ITE aid was shown in the left ear in like two panels, and in avengers assemble v3 and subsequent related infinity comic appearances, there were no visual depictions at all.
however, for his 2-issue arc appearance for this disability month, he's portrayed with a BTE aid again, but only in the left ear.
i guess they mixed up that it had previously been the right ear?
so really, the answer to your question depends on what time period. if it's after his initial deafening in the 80s/90s prior to any retcon, he has two ITE hearing aids. if it's more recent, it's probably one BTE hearing aid, probably on the right ear. but since there's inconsistency, i don't think anyone would bat an eye at clint being portrayed with two.