Just a technicality. As gap is increased x3, force is increased x100. So at least you need to make sure there is no difference greater than x3 or so in your gap.
Also someone already invented this idea somewhere around 2012, here
And someone else filed a patent in 2005, here
So this idea gets reinvented every 10 years or so.
Its hard to test it with casimir effect. Lets consider a version with magnets. If magnets are nearby and at an angle, like V, and attracting they should also move in the same direction, towards the V opening. Like in your example. This is how half of the perpetuum mobile devices with magnets are made.
If we try to 'simulate' it by taking several points, it becomes clear. For simplicity take V with sharp corner.
Lets take 4 points, 2 in V corner, and 2 in V edges. Forces edge-to-corner are within the plane, and act against the material. Forces corner-to-corner act symmetrically, and arent interesting.
Or 6 points, 2 in corners, 2 in the middle of the line, 2 in the edges. Corner-middle are within the line, acts against the material, so are corner-edge. Middle-middle and corner-corner are not interesting. Middle - corner do have force vectors at an angle, so probably it will work. Middle1 -> corner2 we can split into forces within the line thatbare cancelled out by the material, and perpendicular to it. As we consider one side, there is a side force. But it is cancelled exactly as we consider corner2 -> middle1 force. This is similar how it would react if you would connect a tensioned spring acros an angle, from a middle of one side to the corner of another side.
I've invented the magnetic version with angled magnets too when I was younger. And even built it. It didnt work, sadly.
All of these perpetuum mobile machines can be analyzed this way, by calculating forces betwen points. All of the confusion comes when people try to generalize the force and give it a direction, to the larger body than a point.
But I think it is safe to say that ibteraction happens between point-like objects, or spheres. And calculating forces through them helps in such cases. Even if there is just 4-6 points, it can show the situation differently.