According to this Guardian article:

the UN general assembly officially retired the 16th-century Mercator projection in favour of one based on the more accurate 2018 Equal Earth design

UN resolutions are non-enforceable, so I’m sure countries will implement it in different ways (some may not implement it at all). France has already said they will be using Eckert IV which is close to Equal Earth:

If you’re picking to win, this is an excellent write-up: https://www.mayerowitz.io/blog/mario-meets-pareto