As a heads up for anyone who wants to tackle an FM 2023 version of this, hopefully SI have added the details of some of the clubs, but, if not, I have kept my spreadsheet as up to date as possible for the 2022–23 season. I'm personally waiting for the full release date and access to the editor before making my biennial purchase.
Hope the data here is useful for anyone who needs it. Sourced from the Cymru Football App, league and club websites, and the posters of the Non League Matters forums.
Wales Stadiums Lat-Long (2022–23) 2022-10-20.xlsx