I am not sure how this could possibly work. To govern and regulate a public block-chain is fundamentally against what they stand for. A public block-chain-based cryptocurrency is meant to be resistant to government forces. They shouldn't be allowed to enforce rules on who or what you trade.
A better approach would be to regulate the exchanges, which is probably not too far off. However, even in this case decentralised exchanges like BISQ could most likely completely avoid any regulation.