Power BI has some nice handling for date/time fields where you can separate the formatting from the content. I.e. a datetime can be presented as yyyy while still properly populating charts.
The Edit Semantic Field functionality allows you to choose a number of formats but misses a few very useful ones:

It would be great if the following options could be added:
- mmm
- mmmm
- mmm-yy
- mmm-yyyy
- yyyy
Even better if users can specifiy the formatting strings themselves.
Whilst the functionality specifies Tabular-only, I assume it also works for XMLA endpoints