Batch rename file by removing first 6 characters and adding it behind the filename
Yes, one of the ways it can be done in Automator is by using a Run Shell Script action with the example bash script code shown further below.

You can create an Automator Workflow, or Service/Quick Action, workflow.

If you do just a Workflow, then you will need to add a Files &amp; Folders action, e.g. Get Selected Finder Items or Get Specified Finder Items, and then add a Run Shell Script action.

If you do a Service/Quick Action, then you only need a Run Shell Script action.

If you do choose a Service/Quick Action then set it to use files and folders in Finder.

For the Run Shell Script action, have its settings configured as:


Shell: /bin/bash
Pass input: as arguments
Replace the default code of the Run Shell Script action with the example bash script code.


The example bash script code uses shell parameter expansion to slice and dice the fully qualified pathname of the file(s) passed to it into the necessary pieces and then renames the file(s) using the mv command with the -n option, which will not overwrite an existing file, based on the values of the sliced and diced pieces of the fully qualified pathname.

As coded, it uses a regex to only act on files that starts with two digits, followed by a dash, followed by two digits, followed by a dash, followed by two digits, followed by a space, followed by additional characters and a file extension, e.g.: 20-10-03 Testing.zip

Example bash script code: 

    # f = fully qualified pathname
    # d = directory pathname
    # fn = filename with extension
    # n = filename without extension
    # e = filename extension
    # p = filename prefix e.g. '20-10-03'
    # s = filename suffix (filename without prefix, space, and extension)


for f in "$@"
do
    [ -f "${f}" ] || continue
    d="${f%/*}"
    fn="${f##*/}"
    [[ ${fn} =~ ^[0-9]{2}-[0-9]{2}-[0-9]{2}[[:space:]].*\..* ]] || continue
    n="${fn%.*}"
    e="${fn##*.}"
    p="${n%${n#????????}}"
    s="${n:9}"
    [ -n "${s}" ] || continue
    mv -n "${f}" "${d}/${s} ${p}.${e}"
done



The output of which would be, e.g.: Testing 20-10-03.zip



Note: The example bash script code is just that and does not contain any additional error handling as may be appropriate. The onus is upon the user to add any error handling as may be appropriate, needed or wanted.