I’m posting this in case someone else does a search for the same situation and this helps.
I’ve set the system Locale in the OS, and set it in config.php, and set it at language and locale under the invoice preferences, but I don’t think any of these will help the date formatting from the US style because the code that formats the date is in Inc/Claz/Util.php and it says:
$pattern = “m/d/Y”; // 02/13/2020
Just flagging this for the searches and as a possible TODO if anyone else wants to format the dates according to the locales — NOT A COMPLAINT, NOT A BUG REPORT.
All I had to do was change it to
$pattern = “m/d/Y”; // 13/02/2020