Is there any MSFS addon which can display useful airport information in a window, i.e.: wind and weather conditions, air pressure, active runways etc?   Or otherwise a window to see the radio frequencies for ATIS etc?

Greazer.

Little navmap 

The subscription version of the gtn750 mod will do most of that giving a pop up window emulating a gtn750, including METAR and navigraph charts from your navigraph sub if you have one.  They also have a basic freeware version but I do not think it gives you metar/navigraph just basic info like airfield altitude and runway directions.

Note if you are flying out of some obscure private grass strip in Botswana you are not going to get METAR on it, regardless of the addon.

Edited August 4, 20214 yr by Glenn Fitzpatrick