Let's say I have 1000 Euro (in German bank account from legal income) because the German bank's interest is 0% so it is not wise to keep money in my bank account.
In my home country (3rd world country), the bank pays interest around 8%/year, so what I can do is transfer all Euro from my German bank to my home country bank account (foreign currency exchange).
After 2 - 3 years, I'll withdraw all money from home country bank (local currency not Euro) and buy bitcoin via home country service market. Then, I will sell all bought bitcoin in Germany via European service market to gain Euro (at that time, 1000 Euro from the beginning should be like 1200 Euro).
Do you think any problem with this strategy? Is that illegal?
I knew if I hold Bitcoin for more than 1 year, I will not need to pay tax for capital gain in Germany, but will the German bank question about my income when I sell all bitcoins to get Euro?