Any BT adaptors based on CSR8510 A10 chip are not compatible with Continuity. Features like Handoff, Instant Hotspot, Universal Clipboard are not functional, AirDrop is working however if you manually open AirDrop tab in Finder. It is recommended to buy a Broadcom based BT dongle like ASUS BT400.
To enable Continuity if its not active by default, you could either use Clover Configurator's KextToPatch option, or go with https://github.com/dokterdok/Continuity ... patibility
Some DIY workshops located in Shenzhen, China are selling PCIe Wi-Fi + BT AIO solutions on Taobao, not sure if they ship internationally. Basically they took left over AirPort Extreme cards from iMacs or MacBooks, put them together with a PCIe adaptor card with custom design. This card definitely works OOB and fully compatible with macOS.