First of all, I couldn’t find another post where you already discussed this, so I open this post:
I’d like to know if there is any way that Search Engines detect the HTML content generated inside PlayCanvas.
Can you give us any tip to make a good SEO for web pages where the content is mostly shown in playcanvas?
Google will index playcanvas games pages as long as they are linked from somewhere so you will get search results based on your title and description.
If you’re embedding your playcanvas application in a webpage, standard SEO tips apply.