As someone who worked for a trading firm that did some* crypto stuff, you absolutely could sell 2B Euros worth of BTC, in a matter of weeks (contingent on market conditions), without significantly impacting the price.
*Some being trading volumes under but approaching $1B/month, although we didn't really have directional price exposure.
*Some being trading volumes under but approaching $1B/month, although we didn't really have directional price exposure.