Hi Ville,
as far as I know no chance. On the older MHz Cockpits you have been able to use the PPM output of the buddy box. Unfortunately this feature has been removed on the M-LINK Cockpit which means that as soon as the HF module will be switched off the transmitter switches to student mode without the possbility to access any menu for mixing, servos and so on.
If you are interested in I would look for the link from a different forum which shows the only way using a self-made converter consisting of a M-Link receiver, some electronics and a Spektrum TX module. This project might be adusted for the Wea.
Cheers, Matthias