"Avez-vous le même soucis ?"
Oui!
Like @Emiel1 and you, @Julie1519 , I have to explain to guests how the trash works here. Sometimes they don't listen, and so, like you, I am cleaning up and sorting by hand, and it is most unpleasant.
I don't think there is anything Airbnb can do to educate guests about this. Have you been a guest? Guests get an email asking them to read and abide by the house rules, and to be considerate, etc. No amount of extra emails, popups, or online courses are going to educate our worst guests on how to behave themselves.
I do have a checklist on the wall for checkout, and that seems to help a little. Would that work for you?
All we can do in the end, if they refuse to read and listen, is to review accordingly. We can keep it in the private comments if we think it was just a misunderstanding, or we can make it part of the public review if we think what they have done was willfully disrespectful and that they will go on to be bad guests for future hosts. We can take away stars.
I do hope you get some five-star trash-savvy guests this summer!