Tax implications of the interest earned in India

I have some questions regarding tax implications of the income in India from the following sources.

NRE Account (FD and Savings)
NRO Account (FD and Savings)
Mutual Funds

1. Interest in NRE account is non-taxable in India, I assume that I need to pay the taxes for the same in Germany (taxed at 27%)

2. Interest in NRO FDs is subjected to TDS in India at 30%. I assume that I can file the tax returns in India for the same and income up to Rs 250,000 is exempted so I can get the TDS back. Am I right here? If I do so, do I need to declare this income in Germany? What’s the best way to handle it?

3. Mutual funds, If I understand correctly we don’t need to pay any tax in India if the funds are not sold. However, I think I need to declare my investments and pay taxes on the expected gain in Germany. Is that correct?