Let's hope so! FME support would really help users move to the new standard
Hello @virtualcitymatt & @Takashi Iijima , fairly certain development is starting to work on this now. Not sure if it will make it into 2022.0 or 2022.1 however.
Note* we do have limited support for R/W CityGML3 right now, with the GML R/W uing CityGML3 schemas. Also, we don't support appearances yet for this. Hope this helps, Kailin.