Hello. I’m wondering about item (author) exclusivity: if an author is selling (exclusivly) a Wordpress Theme on Themerofest, while selling it’s HTML (or other CSM) version elsewhere, e.g. on their website, is that author considered exclusive or non-exclusive on Themeforest?
You can’t be considered exclusive only when you are selling the same theme for the the same cms on other marketplace.
Because, when you build a theme for WordPress, then you build it for Magento or Joomla, in the end you will have 3 different products for selling.
This is why I say that your case is allowed, in this situation you are called exclusive.