Yes, that’s a Word weidness.
There’s a trick: You can create a calculated field on the report, a Text field that uses an expression like this:
FORMAT(Header.Posting_Date)
(The element might not be called “Header” in the report, adjust the code to reflect the right name)
Check this: https://learn.microsoft.com/en-us/dynamics365/business-central/dev-itpro/developer/devenv-format-property#standard-date-formats
You can even format the date to your liking:
FORMAT(Header.Posting_Date,0,4)
That will result in something like 5. April 2021