How would genetic variation be affected if, during meiosis I, maternal chromosomes always lined up together on one side of the metaphase plate and paternal chromosomes always lined up on the other side (ignoring the effects of crossing over)

The chromosomes are pulled away from one another from the metaphase plate. Subsequently, all the chromosomes to 1 side are pulled one way, and all the chromosomes on the opposite side are pulled the other way. In the long run, every haploid cell would possibly contain either just maternal or fatherly chromosomes if traverse didn't happen.

The gametes contain either paternal or maternal chromosomes only.

Explanation:

Meiosis is a cell division process that occurs when a four daughter cell arises from a single cell that divides twice.

During meiosis, the identical sister chromosomes chromatids are held together by the chaismata. As the process progresses the chromosomes are separated from the identical pairs by microtubules, each moving away on its own.

These separated chromosomes contain haploid nuclei, each nucleus contains either the paternal chromosomes or the maternal chromosomes.