Replace would work great. You can chain functions together, so here we’ll be chaining 7 replace functions:
[[Now.getDayOfWeek().replace('Monday','Mo').replace('Tuesday','Di').replace('Wednesday','Mi').replace('Thursday','Do').replace('Friday','Fr').replace('Saturday','Sa').replace('Sunday','So')]]. [[Now.getDate()]].[[Now.getMonth()]].[[Now.getFullYear()]]
...
This will give you So. 19.5.2019 for today’s date. (I don’t know much about German dates: I’m assuming the day-of-month precedes the month.)
How it works:
Say it’s Sunday. getDayOfWeek() will return ‘Sunday’ which will be passed through the first replace() that tries to find ‘Monday’ within ‘Sunday’ and replace it with with ‘Mo’. The result of this replace() will still be ‘Sunday’ since the replace() found nothing to replace. Then the ‘Sunday’ result of the first replace() is passed through the next replace(), which tries to find ‘Tuesday’ in the ‘Sunday’ string and replace it with ‘Di’. This replace() returns the string ‘Sunday’ since it found no ‘Tuesday’, so the ‘Sunday’ result of the Tuesday replace() gets passed to the replace() seeking ‘Wednesday’, and so on down the line until the last replace() actually finds ‘Sunday’, and replaces it with ‘So’.
If today is Monday, the first replace() would succeed, passing ‘Mo’ through all of the subsequent replace() functions, which all will return ‘Mo’ since ‘Mo’ doesn’t contain ‘Tuesday’ or ‘Wednesday’ or Thursday or …