Hi Paulo,

Thanks for your interest in our plugin.

For your information: 

• In the free version of our plugin, only simple and subscription products can be searched and added. 
• Instead, free users can now add unlimited products as they prefer. 
• Variable products and variations are only available in the Premium version.

Note: Some types of subscription products are not fully compatible with our plugin as well. We can offer customization service to make it work if you are a Premium user and provide us with access to the admin area.

Honestly, I am not very clear about your question yet. Did you mean you would like to use 2 attributes color and sizes in variable Bought Together products? Well, the displayed atttributes are based on the actual attributes you have added to your individual variable products. You can display any kind of attributes, be it size, color, pattern, delivery method, etc. and as many attributes as you want.

In case you need further instructions on this plugin, please refer to this guide: https://doc.wpclever.net/woobt/bought-together-setup/