Most all of the tutorials for this say to use a ESP-01s with a voltage regulator but I Wanted to share a different solution I have found. I had some of these Amazon esp8266 hi let go chips laying around with the added benefit of being able to run on 5v. I found they fit pretty nice if you cut a hole in the top and pass the antenna out. It looks like they don't obstruct the airflow too much that way. They work great soldered directly to the Ikea board and also work for the constant 3.3v noise hack if you wire the fan positive to the 8266's 3.3v pin.
Board used: HiLetgo 3pcs ESP8266 NodeMCU... https://www.amazon.com/dp/B081CSJV2V?ref=ppx_pop_mob_ap_share
Instructable tutorial: https://www.instructables.com/Connecting-a-IKEA-Vindriktning-to-Home-Assistant-U/
I've also become interested in adding some air quality sensors recently (from the Canadian wildfires). I just bought some Nova SDS011 modules with USB adapters. Doesn't come with a nice case but should require less hacking. Probably ends up similar in price.