A Static Mesh Component can only have 1 static mesh instance. The “Build Ghost Mesh” is just a reference you made to a single static mesh component. Thus, that variable, which is a single component reference, can only contain 1 static mesh within it. You would need to add multiple static mesh components, and set the different static meshes with each one of those components (1 mesh per component), like this:
if you mean the build ghost mesh variable just put them in an array too and then the same with the transforms, if they vary somehow you can use the index to find them.
im not sure exactly what your doing and why from the screenshots but cant see any reason it wouldnt work