I am aware of the existence of currency exchangers, and I am familiar with the process of converting money into the same kiwi or poison. However, when it comes to transferring a significant sum, there is a high chance that the account will be frozen, making it incredibly difficult to provide a legitimate explanation for the source of funds. Consequently, I have several questions:

What is the most optimal method for withdrawing eth/btc cryptocurrencies?
What is the most effective approach to transferring a substantial amount and actually receiving it in physical form?
Which payment system would be the most suitable for such transfers?
Are there any specific countries known for facilitating such transactions more smoothly?

Is LocalBitcoins no longer a viable option? It might be worth reaching out to your circle of friends as you never know who might be interested in acquiring cryptocurrencies.

Alternatively, exploring the darknet could be advantageous as it offers numerous "laundries" that specialize in converting cryptocurrencies, typically bitcoins, into physical cash.

Bitstamp provides the option to withdraw funds to a bank account using Swift, offering good liquidity and relatively low fees.

In my opinion, it would be more advantageous to convert the funds into US dollars and withdraw them to a card. The location of the country doesn't make a difference in this regard. However, the real challenge lies in finding ways to accumulate a substantial amount of funds rapidly.

Cryptocurrency exchanges of high repute operate with transparency and are subject to regulation by authorized entities.

Earning profits through cryptocurrency trading is indeed feasible, making it crucial to comprehend the process of cashing out bitcoin or any altcoin (referring to any cryptocurrency other than bitcoin). Depending on the exchange's functionality, various options may be available:

1. Integrated Direct Purchase and Sale Service: Here, you can sell bitcoin for fiat money directly within the exchange. The process involves purchasing the desired fiat currency using bitcoin at the prevailing exchange rate. Subsequently, you can withdraw the fiat funds through a chosen method such as bank transfer or to a bank card.

2. Peer-to-Peer (P2P) Exchange: In this scenario, you sell bitcoin to another user on the platform. Typically, the exchange provides a dedicated service where users can place orders for buying or selling supported cryptocurrencies and fiat currencies.

Additionally, you always have the option to sell bitcoin for fiat as part of your trading strategy. If you currently don't require exchanging cryptocurrency for fiat, you can withdraw bitcoin to a cryptocurrency wallet.

When it comes to cashing out Bitcoin (BTC) or Ethereum (ETH), there are several methods you can consider. Here are a few common approaches:

1. Cryptocurrency Exchanges: The most popular method is to use a cryptocurrency exchange that supports fiat currency withdrawals. You can sell your BTC or ETH on the exchange and then withdraw the funds to your bank account.

2. Peer-to-Peer Trading: Another option is to find a trusted individual who is willing to buy your BTC or ETH directly with cash. Platforms like LocalBitcoins and Paxful facilitate peer-to-peer trading and provide escrow services for secure transactions.

3. Over-the-Counter (OTC) Trading: OTC trading involves dealing directly with a broker or institutional trader. This method is suitable for large volume transactions and offers more personalized service, but it may require meeting specific requirements and higher fees.

4. Bitcoin ATMs: Bitcoin ATMs allow you to convert your BTC into cash. These machines are available in various locations and provide a way to withdraw physical currency.

When transferring a substantial amount and receiving it in physical form, there are some additional considerations:

1. Security: Ensure that you have adequate security measures in place to protect your funds during the transaction and afterward. This may include using reputable platforms, implementing secure wallets, and considering physical security options.

2. Legality and Compliance: Be aware of the legal and regulatory requirements regarding large transactions and money transfers in your country. Ensure that you comply with the necessary regulations and disclose the source of your funds as required.

3. Privacy: Understand that cashing out a significant amount may attract attention, as financial institutions and authorities may scrutinize such transactions. It's important to be transparent and provide legitimate explanations for the source of funds to avoid potential issues.

Regarding the most suitable payment system and specific countries for cashing out cryptocurrencies, it depends on factors like your location, preferred method of withdrawal, and the legal and regulatory environment surrounding cryptocurrencies in different jurisdictions. Researching and consulting with professionals in your region would be the best approach to determine the optimal method and country for your specific circumstances.