Are you kidding? Kernel and drivers are the same, so there will be no significant difference. For what would be bluetooth on board then?
EDIT: As I said - there is no difference. I’ve just tried and both bluetooths - onboard and external connected via USB - are not fully working. I mean they connect to the phone losing connection from time to time but there is no way to use Rock Pi as Smart Lock for Mi 9 phone. Also there are general problems Rock Pi and Mi 9 finding each other.
Commands I’ve used:
apt install ap6256-firmware
apt install bluez
apt install bluez-tools
apt-get install bluetooth bluez blueman
apt-get install broadcom-wifibt-firmware
blueman-manager
bluetoothctl
brcm_patchram_plus1 -d --enable_hci --no2bytes --use_baudrate_for_downloade --tosleep 200000 --baudrate 1500000 --patchram /system/etc/firmware/BCM4345C5.hcd /dev/ttyS0 > /dev/null 2>&1 &
bt-device -l
btmgmt
echo 1 > /sys/class/rfkill/rfkill0/state
hciconfig
hciconfig -a
hcitool
hcitool -a
hcitool dev
hcitool scan
service bluetooth restart
sudo apt-get install -y rtl8723ds-firmware bluez
systemctl reenable bluetooth
systemctl restart bluetooth
systemctl show bluetooth
systemctl start bluetooth
systemctl status bluetooth
systemctl stop bluetooth