https://www.mangago.me/read-manga/musebenake_junjou/
https://www.mangago.me/read-manga/shishi_no_odoriko/ (this surprised me alot )
https://www.mangago.me/read-manga/aimai_na_wolf/
https://www.mangago.me/read-manga/yakimochi_wa_kitsuneiro/
https://www.mangago.me/read-manga/kamikudaite_aio_oshiete/
https://www.mangago.me/read-manga/oyasumi_itoshiki_kotori_sama/
https://www.mangago.me/read-manga/tsuki_wa_michikake_kemono_no_koi/
https://www.mangago.me/read-manga/neko_to_mahou_wa_kiss_de_hodokeru/
you can find more if you search "animal characteristics" on the tags search
https://www.mangago.me/read-manga/ookami_sama_no_ichizu_na_bouai/
https://www.mangago.me/read-manga/otoshi_ai/
Hope this helps with your research(● ̄(エ) ̄●)
A beast x human yaoi manga where they have sex while the other one is in his beast/animal form
(for research purpose)