No, only 0.4, 1.0 and 2.0 are currently supported, as per the documentation.

This question has popped up before, and in their response Safe has indicated that they are working on it: "Not sure if it will make it into 2022.0 or 2022.1 however. " Apparently it did not make it in to 2022.2 either.

You might vote for this Idea to show your interest: AC Idea: Add CityGML 3.0 Support

The XML/GML encoding ​of the CityGML 3.0 standard is not yet published/released by the OGC. https://www.ogc.org/pressroom/pressreleases/4789

Recently the deadline for public comment has finished though - it is expected that the GML/XML encoding ​standard will be released early next year.

I suspect that Safe would wait for the official Encoding release before adding support. ​

Sounds reasonable :-)

Thanks for your responses