@
rudderrudderrat,
A graphic of the Airbus SS arrangement was posted by
A33Zab in
AF447 Thread No.5.
With the addition of Synchro motors on each axis and interconnected to the opposite SS, the movement of each stick would then follow the other. Dual inputs would result in the appropriate feedback. However, realistic control surface feedback would be more complex, but if the FBW existing control surfaces positional feedback had inertial data added to it, a control transformer could be inserted into the Synchro couplings and a more realistic "feel" would be available to the sidesticks.
That's a simplistic example, and sophistication would improve it.
The disadvantage is as usual - extra complexity and weight.