A separate question, is there way for small user like me to hedge btc price risk in a short time frame? Let's say I buy 0.1 btc in China. I know takes 30 mins for trade to settle/escrow then transfer to US exchange. Within these 30 mins is there a cheap way for me to lock in the price of btc? One idea I have is use the Defi loan in Ethereum:
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Does this look practical?
You're over-complicating things with the "defi" route.
Simply buy the BTC, and when you have access to the BTC, simply withdraw the coins immediately to the US exchange. If you're going to send
from an exchange, chances are, the withdrawal fees are going to be slightly on the higher side by default as to not take you too long to receive the coins.