1- Theme Options > WooCommerce > Shop elemets > Sale & Out of Stock > “Sale” Label Text.
WPML > String translation > scroll down and press on “Translate texts in admin screens” link. You’ll see a list of fields, choose the fields you’d like to translate. For example – http://prntscr.com/10gxxqu After that go back to the String Translation section and translate the necessary content.
2- I don’t see any issue it is working fine I have checked the link that you shared and here is the resulting image: https://i.is.cc/2eRNweVv.png please check back to your site after clearing the browser cache.
3- Actually you are using 2 language plugins on your site and which might conflicts with one another, so always use the one, If you use the WPML then try not to use the Loco, OR else try to contact the WPML support.
4- Sorry to say, that there is no option in the theme for this because the form is coming from the WooCommerce plugin and our theme does not have any influence on it. Changes require customization.
5- The thing you requires is already done on your site as you can see in this video: https://streamable.com/n4elk0
Regards 8Themes Team.
One standard license is valid only for 1 project. Running multiple projects on a single license is a copyright violation.