The Magento 2 Upsell product Extension can work with magento 2 templates, with most 3rd-party plugins. If you come across a compatibility issue with any third-party module, we’ll definitely try to help you. If you face any technical issues, please create a ticket. We will support you out of the issue. In case the issue related to the 3rd party plugins, our dedicated dev can can make a study and fix it for you with extra fee if required