Woman-Related refers to genders that are related to, but not aligned with, being a woman. Woman-related people are not woman-aligned at all, but feel as though they're in the same or a similar "category" as women. Similar to how red and yellow are different colors, but they’re both still considered “warm colors” and in the same category, or how hyenas and cats are extremely different animals, but are both a part of the same suborder. It is something completely separate, but connected in some way. Woman-related and fem-related are not the same term, as being a woman and being feminine are not synonymous.
The male equivalent to this is man-related.
Some identities that may fall under woman-related include:
The woman-related flag was made by Tumblr user quiet-times on November 1, 2020. The stripes have no written meaning, but are presumably to represent colors that are similar, but different, to traditionally feminine colors, like pink.