I've done this, on an SSD at least.
Probably on your drive right now there's some kind of corruption going on; I'd bet that Untitled and CRE are sharing the same UUID... I've had that happen with some interesting results.
If you want two partitions, with one as APFS:
Reformat the whole disk, creating two partitions - the one you want to be APFS should be formatted as HFS+.
Once that's done, format the HFS+ volume as APFS. That will create a container, and then the final volume will be inside that.
In the pictures, you can see I have three partitions. In the first image, it's apparent that there are four volumes, and the two under "Container disk1" are APFS.
If you want two APFS volumes:
- Reformat the whole disk - that the disk level, as in disky, not disky1 - with one HFS+ partition. You could go straight to APFS but I think this will prevent potential issues...
- Format the whole disk as APFS. You should then have a three level tree - disk, container, and volume.
- Now you can create your second APFS volume. Select the "Container" disk, click on the "Edit" menu in the menu bar, and click "Add APFS volume." That will create what behaves as a second partition, but it will share available disk space with the first APFS volume.
You can set minimum and maximum sizes for the volumes too if you like.