Is there a portable air conditioner with a humidifier feature?

An air conditioner is, partly a dehumidifier. Part of how it works is to remove humidity from the air so adding humidity would be counter productive.
If your air is hot and dry you might consider an evaporative cooler instead of an air conditioner.
I used to live in a house that had both. The evaporative cooler was more energy efficient but didn’t work well above 90–100 degrees. I only had to use the AC on exceptionally hot days.

No. Dehumidifying the air is what makes A/C units cool the air: buy drying it and making the sweat evaporate off of your body faster making you cool.

@kritiper Actually that’s backwards. An A/C cools the air and coincidentally water will condense on the cold parts and the air will have less water in it. The air is cooled and as a by-product the moisture is also reduced.
You will feel cooler mostly because the air is in fact cooler. Dehumidifying does help most folks be more comfortable as well.

@Judi is correct a typical A/C is also a dehumidifier.

@dabbler – You contradict my teachers at Denver Automotive and Diesel who taught me air conditioning principals and theory. Yes the air is cooled. But the increased dryness of the air increases the evaporation of the sweat on your skin making you feel cooler. If the humidity was still at, say, 100%, the air could be cooled to 50 degrees but you would hardly notice.