Earlier quoted context omitted.
How do you suppose this would be implemented? These things only affect a very small niche audience. Most people don't care what is going on in HK and even less people will care about this incident.
I feel like social media is the best legal venue for it. Start sending messages to every game dev, project manager, and director at these companies asking them why they support the totalitarian oppression of HK. Ask them what they are currently doing to limit the influence of totalitarian regimes on their corporate policy. Make the issue personal for the companies by fomenting discontent from within.
But the only options available to the employees from that point onwards is group organization (eg. unionization) which is itself politically controversial and prone to ruining their careers (see: google employees' organizing efforts resulting in the majority of the original organizers being foistered out of google) or leaving which puts their livelihoods in jeopardy as they abandon one of the biggest employers of their industry..