demetK

Problem:
We are building a website using a theme that it's not on your compatible theme list. Would this create a lot of issues to deal with during translation?

Solution:
If the theme is not added to the list of compatible themes with WPML, it doesn't mean that the theme is not compatible with WPML but means that our compatibility team didn't test it.

I also see that the theme author mentions that it's compatible with WPML, so I think the only way is to use the theme and test it.

I couldn't find any support tickets that report any issues with this theme. So I suggest trying it and then contacting the theme authors for any issue that appears and getting their response.

Also, if there's anything that we will be able to help with after their response, we would be happy to do that.

I'd suggest that you also recommend the developers of the theme to join our 'Go Global' program (https://wpml.org/documentation/theme-compatibility/go-global-program/) where our Compatibility developers can test their theme to make sure that it is 100% WPML-Compatible so that we can also add the theme on our site here:
https://wpml.org/theme/