How do I brace shed walls against shear when sheathing cannot overlap rim joist?

I’m building an 8′ by 13.5′ shed with a loft. I posted previously about the floor frame being slightly larger than the planned floor. Below is the intended floor framing, as seen in the plan:

Here is the current execution (joists have been installed as above but are omitted from the diagram; red area is where subfloor and walls actually sit):

Consequently, the outer face of each side wall (2×4 thickness) is inset about 3" from the outer edge of the beam below it (three sistered 2x6s). Here is a cross-section of a side wall:

I have nailed the bottom plate to the 2×6 below, but could not overlap the sheathing past the bottom plate and nail it to the rim board (like I did on the rear wall) because of how the rim board juts out. I plan on adding flashing to avoid moisture seepage into the plywood.

The current connection between walls and floor is rather dinky and I would like to ensure that shear bracing is adequate, especially since I live in a relatively earthquake-prone location. Can I use another method, e.g. using steel strapping to attach the wall framing to the rim board at studs? If so, can I bend the strapping so that it conforms to the outer surface of the rim board and wall?