It looks like that both .cft and .cdt files are actually templates from various CorelDRAW versions or features, so perhaps some kind of cft to cdt conversion is doable in sense that you can transfer some elements manually to create a new template based on the existing one. Unfortunately, we have not found any specific information about this, so if you are indeed in need fo such export or struggle with it, it would be perhaps best to reach out to the Corel support.
Updated: July 18, 2023