OpenGL - Batch Renderer with Multiple Objects and their Transformation Matrices

Hi, I have created a possibly incomplete Batch Renderer(linked below). But, I have just come to a standstill as to how I apply a Transformation Matrix if their are multiple separate(different pos, rot, scale) objects in the same batch. How do i do this? Do i apply the objects transform(pos, rot, scale) to each of it vertices as it is put into the batch? If so how(rotation and scale - position is just added)?

Batch Renderer Code

Thanks.