More than tangency continuity a curvature continuity would be even better…
Then loft works with a list (a single branch) of curves. Each different list (branch) will be a different resulting surface.
If you add a “Flip matrix” before your loft component it will make something.
I think it would be best for you to first rebuild your polysurface into a single periodic surface with tangency/curvature continuity at the seam, and then work with that instead.