Automated tagging regular ex

How can i use regular expression on automated tagging?

I want to add the “Rechnung” tag to all files if the word “Rechnung” appears in the name. How can i do that? I have absolutely no idea about regular expression.

Will automated tagging work on group folders and external storage?

Go to the NC flow settings and add an “automated tagging” flow.
Set filter to: Filename -> is -> /Rechnung(.*).pdf/ -> Rechnung
This will automatically set the tag “Rechnung” to all pdf files with string “Rechnung” (case sensitive) in filename. The “is” will switch to “matches” as soon as you insert a regex to the filter condition.
If you want to go further with NC-regex, try with PHP flavor.
Automated tagging will work with group folders. I’ve not tested external storage yet.