It depends on the QR code on the security devices. 

If there is no Home logo on the QR code, it means that the camera/HomeBase cannot be added to the Home app directly. When you remove your camera in Eufy app, all the information including on-device information will be reset (such as Wi-Fi info). So, once you remove your camera from Eufy app, your camera in Home app will stop working too. 

If there is a Home logo on the QR code, you can add the device to HomeKit directly. However, the HomeBase with home logo has been discontinued. At present, the HomeBase sold in all sales channels does not have a home logo. But the method in this article is still applicable to HomeBase with home logo printed.

For how to connect your HomeKit enabled devices to HomeKit, please refer to How to Setup HomeKit for HomeKit-Enabled Security Devices.