Is it possible to share the German charts with someone else with a different login? If You use it less than once a Year, it almost doesn't make sense to buy it alone.

If you use it less once a year, you won't buy it every year, correct? Frankly, you are talking 59 Euros if I remember correct - in aviation and flying such peanuts are not even worth a single thought - my2cents.

There's no SkyDemon feature for doing what you ask; we license those charts per user, we obviously we need to abide by the licensing terms set out by their publisher. We do sell them for substantially less than practically any other source, though.