For (2) - obvious answer here is crypto but again, the crypto market might implode because if (1) actually happens, the US gov is extremely incentivized to make crypto ownership and trading illegal.
Alternately, in the event of a dollar default - the world may not be conducive to the capex+energy expenditure required to mine crypto. If interest rates went to 20-30%, I’m not sure that crypto mining would be a viable concern - causing instability throughout the crypto world.
That being said, whether crypto is a good hedge or not really depends on whether it’s worth putting money in today - regardless of the potential for US default. Particularly in comparison to Yen, euro, and yuan assets.
Says you, and without even the hint of an argument to back your position.