I recently connected the popular Zigbee version of the IR Blaster to my Home Assistant. I decided to mount it on the living room wall, close to a 230V socket, as this suited me best. My first instinct was to simply stick it to the wall with double-sided tape. However, I quickly realised that I wouldn't have access to the button on the back of the device. I also wanted a sleek, flat solution that would not obstruct the signal.
So I designed my own magnetic mount. As well as the printout, you will need eight small 3x3mm, 3mm diameter, cylindrical magnets: https://www.aliexpress.com/item/1005009535032247.html

The magnets fit quite tightly; you can secure them with a drop of superglue if you wish.

You also need to take care of their polarity during assembly.