macOS not allowing to change the sequence of partitions from command line!
Since the volumes are about the same size, you can use the Disk Utility application to "Restore" the macOS volume from the macOS 2 volume. You basically will then have duplicated macOS 2. You then can delete disk0s4 and expand disk0s2 to recover the free space.

All these operations can be performed using the Disk Utility application.

If you are wish to use the command line, then here is the command to clone the volume labeled "macOS 2".

sudo asr restore --source "/Volumes/macOS 2" --target /Volumes/macOS --erase



  Note: The above command also clones /dev/disk0s5 to /dev/disk0s3.


The command to delete /dev/disk0s4 and expand /dev/disk0s2 is given below.

diskutil mergePartitions FREE "" disk0s2 disk0s4  



  Note: The above command also deletes /dev/disk0s5 and relocates /dev/disk0s3 to be below the expanded /dev/disk0s2.


The clone/restore operation could be done while booted from /dev/disk0s5. The merge operation could be done while booted to /dev/disk0s2.