Thanks for your very helpful article. I’m using this plugin https://wordpress.org/plugins/wp-optimize-by-xtraffic/ to optimize the image on my wordpress website. You can try this plugin, it’s great 
Thanks for your very helpful article. I’m using this plugin https://wordpress.org/plugins/wp-optimize-by-xtraffic/ to optimize the image on my wordpress website. You can try this plugin, it’s great