Crows are pretty smart animals, and they can be easily trained. Even nowadays, people can train them to follow certain people for example, basically ‘spying’ on them, they can be trained to ‘talk’, and with enough patience you can train them to press buttons or do a small sequence of things.
So yes, in theory it’s possible to train them to fly around with a small camera.
Looking at the other birds we have, all of them should be able to carry a small spycam ; after all, those only need to be as big as a button or so to work. However, the training might be the problem here, out of all birds we currently have ingame, none seem…smart enough. We have geese, ducks, chicken, and so on, none of them would be smart enough to come back to you, at least in my opinion. And some, like the chicken, wouldn’t be able to fly very long at all.
We do have a Cockatrice and it’s chicks though ; since it’s a mythical animal, we wouldn’t really >know< how smart they are or how long they could fly, so…that one is an option i guess.