I've hit a wall or two trying to embed the old flappycoin game into either site.

The new Google Sites doesn't support custom JavaScript nor iframes. For the Wordpress site it would require installing a plugin, which requires upgrading to the business plan. At some point I thought I found a workaround as iframes worked in preview mode, but then it would replace the iframe with a plain hyperlink as soon as I hit the Publish button.

I guess we shouldn't expect much from free hosting. Meanwhile here are the browser games I've found and built off Github to date: https://hanzou-x.github.io/