• https://www.amazon.com/dp/B095H8GT32
• https://www.amazon.com/dp/B097DRQTJL
• https://www.amazon.com/dp/B09YVJ277X
• https://www.amazon.com/dp/B07MJ4SY4M

Every element of the hood system flow path, from hood filter baffles or mesh, hood transitions, straight ducting and bends, duct cap, and means of returning outside air to the kitchen constitute elements of pressure drop. The more of these one has, the more powerful the hood blower has to be to achieve a desired/necessary flow rate (CFM) that will ensure capture and containment of cooking plumes. Hence, any scheme that hides the vent at the cost of pressure loss is your enemy.

The vent type most likely to be typical for your use is shown on this page: https://luxurymetals.com/range-hood-vents/wall-vent-stainless-steel-6-inch-group-wall-vent-stainless-steel-6-inch-group.html, as an example. If painted wall color it would not be too obtrusive, in my view.

For true hiding, one would get the duct into the attic and thence to the roof where a roof vent could be used, possibly opposite the street side. Larger ducting would be preferred in this case due to the possibly long duct run.

Thank you Kaseki!