Can you not use OSX to perform the conversion for you in place?[1] There should also be a `diskutil` command that does it as well. Then you get snapshots and better volume management.
As always do your research first, this conversion is a one-way thing.
As always do your research first, this conversion is a one-way thing.
[1] https://datarecovery.wondershare.com/apfs/how-to-convert-hfs...