Ubuntu – Exec command for kde plasma to enable remote host controller(virtual desktop session)

I want to access my KDE Plasma desktop remotely on my Android and so I've installed Chrome remote desktop app in Chrome (latest versions). I followed the official tutorial but there's need to enable computer at remote desktop host controller so to do they explained to create virtual desktop session.

Create a virtual desktop session

1. Look in /usr/share/xsessions/ for the .desktop file for your preferred desktop environment. For example, Cinnamon has a file named
   "cinnamon.desktop" with the following command:

    gnome-session --session=cinnamon`
   

2. Create a file called .chrome-remote-desktop-session in your home directory with the following content:

    exec /usr/sbin/lightdm-session "<YOUR_EXEC_COMMAND>"
   

3. Replace <YOUR_EXEC_COMMAND> with the command at the end of your .desktop file. In the example for Cinnamon, the correct command is

    exec /usr/sbin/lightdm-session 'gnome-session --session=cinnamon'
   

   Desktops require some additional code. The full command is

    DESKTOP_SESSION=ubuntu XDG_CURRENT_DESKTOP=Unity XDG_RUNTIME_DIR=/run/user/$(id -u) exec /usr/sbin/lightdm-session 'gnome-session --session=ubuntu'
   

4. Save the file called .chrome-remote-desktop-session​.

So I did unsuccessful try with

exec /usr/bin/startkde  '/usr/bin/startkde'

and

exec /usr/share/sddm  '/usr/bin/startkde'

I used sddm cause there's no lightdm in KDE Plasma.
I've followed steps but don't know the Exec command for KDE Plasma for plasma session. So what proper Exec command is there to successfully create virtual desktop session?