It depends on the construction of the rotor if the bending moment in the generator shaft becomes too large at high wind speeds. If the rotor has a diameter and height of 1 m, the resulting thrust on all blades will exert 0.5 m from the bottom side of the rotor. If the whole Darrieus rotor is mounted above the generator, this long distance will certainly give a too high bending moment in the shaft at high wind speeds. It might be that your Darrieus rotor has a horizontal frame half way the rotor height and if this frame is mounted on the generator hub, the bending moment will be much smaller. But now the generator and the tower pipe will give a lot of turbulence at the lowest halve of a blade when the blade is at the backside of the rotor.
A Darrieus rotor with a swept area of only 1 m^2 will run at very low Reynolds values when it is starting. So the aerodynamic drag on the airfoil will be large as the blade will stall at a large part of a revolution. I expect that the sticking torque of the generator of only the bearings and the shaft seal will be too high to let the rotor start, whatever construction the rotor may have. The generator is meant for a HAWT with a rotordiameter of about 2.2 m and the starting torque of such a rotor is large enough at low wind speeds.