Location of extractor hood vent

Thats not really very helpful. One answer would be to fit a snorkel to the vent pipe taking the outlet up and away from the doorway, as you would with a boiler flue

If you had a neighbours smells blowing into your house would you think that ok?? I think you have answered your own question 😊

Unfortunately because of the actual place the vent needs to be placed for a kitchen extractor there’s not much that can really be done because I doubt very much your neighbour will go out their way to add cash to sorting it out and would also look pretty messy too having duct pipe running on the outside of the property. The easy option is to use a recirculated carbon filter and change every few months but then again a doubt your neighbour will be will to pay extra cash all the time to do this.