You may be interested in a paper Thomas Negal wrote about 50 years ago called “What is it like to be a bat?”

www.sas.upenn.edu/~cavitch/…/Nagel_Bat.pdf

It’s not just about emotional states, which we can observe the behavioral states of but don’t know what it is like to experience as other animals. It’s about experience and consciousness which I think speaks to the underlying question of when other animals experience an emotional state if we can relate it to our own phenomenology for similar appearing states.