I sold BTC for EUR fiat in Aug 2023, the BTC in the wallet had been held for more than 365 days.
In Dec 2022 I sold BTC for EUR fiat from Different BTC wallet.
Is the tax to be paid 28% or 0% for the BTC sold in Aug 2023?
If the BTC you sold in August 2023 was purchased/acquired before August 2022, then you will not pay any tax.
All sales made before 2023 are not counted.
Therefore, if you had this BTC for more than 1 year (365 days), you will not pay any tax.