Woman-related refers to genders that are related to, but not aligned with, being a woman. Woman-related individuals are not woman-aligned at all, but feel as though they're in the same or a similar "category" as women.
In the same way that red and yellow are different colors, but are both still considered “warm colors”, or that hyenas and mongooses are different animals, but are both a part of the Feliformia suborder, being woman-related is completely separate from being a woman, yet the two are in some way related.
Woman-related and fem-related are not interchangeable, as being a woman and being feminine are not synonymous.
Its male counterpart 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.