(1.) Freeze the overseas bank accounts of Mainland leaders, their families, and any person or entity found to be acting as a front for them. No more golden parachutes for dictators and their buddies.
(2.) Refuse visas to Mainland leaders, their families, their friends, etc. Make it clear that Mainland nationals in these categories will be kept out of the USA/UK/etc. even if they attempt to slip in under other passports (e.g. HK, for example). No more luxe prep schools and Ivy League educations for dictators' kids and their buddies.
(3.) Publicize the identities of the bank account holders and the amounts in these accounts within the PRC if, by necessary, air-dropping pamphlets from unarmed drones or painting the information on the exterior walls of the US/UK/etc. embassies and consulates. Do the same for leaders whose spawn are receiving expensive overseas schooling and missing out on oh-so-essential "national education".