Hey folks,
I'm asking for a friend and would really appreciate any advice from those with experience in crypto privacy or off-ramping.

A friend of mine (19 years old, student) recently won a mid five-figure sum in ETH via a gambling site (Stake), though the account was in someone else's name. The ETH is now stored on a self-custodied MetaMask wallet, not tied to any identity or KYC.

He’s hoping to cash out a portion of it – either as cash or a quiet bank transfer, ideally with <1% fees – to fund small personal projects, set up a few savings plans, and help renovate his parents' home.

However, he's in a bit of a sensitive situation:
He currently receives government student aid (BAföG) in Germany, which has strict wealth/income limits. If he suddenly shows large deposits or assets, it could disqualify him or trigger repayment.

His main concerns:

If he uses a KYC exchange, even for small amounts, could authorities link his wallet to him?
Could banks or tax offices freeze his account or ask for explanations if more money starts showing up?
Would this be counted as "assets" and disqualify him from his student support?
His parents can't act as proxies, as they also have low income and don’t want to risk anything.
Possible solution:

We were thinking of P2P trading – selling ETH for cash (in person) or bank transfers to third parties, without using a centralized exchange.

But now he's asking:

What are the most reliable, anonymous, and KYC-free P2P platforms for ETH or BTC in Europe?
Should he convert ETH to BTC first? If yes, how to do it without linking it to himself or using KYC exchanges?
How does an in-person P2P trade actually work? Any dos & don’ts to stay safe and not get scammed?
Or… is there a better/cleaner way to go about this?
He’s not looking to avoid taxes, but just wants to stay under the radar and avoid issues with banks or government benefits.

Would love to hear your thoughts or tips – especially from people who've done similar things.

Thanks a ton in advance! 🙏