Combine images using CSS sprites issue in gtmetrix can be resolved using Cloudflare CDN with free plan?
No, you’d need to combine images with CSS sprites at the origin. The resulting image will be cached by Cloudflare based on usage.
Cloudflare does offer on Pro Plan or higher a service called Mirage, which for mobile connections will also streamline requests into one. Not sure if GTMetrix will be able to detect it, though.