Doesn't the shinigami eyes extension mark transphobia to trans men as green?
Hoo boy. This sure is a question! I'm gonna try breaking this down a bit.
Shinigami eyes is more useful for the red marks, not the green marks
The marks ARE community sourced, so it's not impossible
Honestly, though, that doesn't sound very likely! I think you're probably hearing talking points from people who don't like it when people push back against transmisogyny
I'm not sure how much you've been following the discourse, but there's this ongoing argument about the concept of "transandrophobia" as a counterpart to transmisogyny.
Transmisogyny is the intersection of two different kinds of sexism - oppositional and traditional. Traditional sexism is the idea that masculinity is superior to femininity. Oppositional sexism is the idea that male and female are rigid and mutually exclusive.
Trans men obviously suffer from transphobia and discrimination, and in the lens above, they are victims of oppositional sexism constantly. However, they are also beneficiaries of traditional sexism; there are advantages that trans men specifically have over trans women, even if access to those privileges is limited.
You can also understand transmisogyny as the unique phenomenon that arises from the intersection of transphobia and misogyny. In both of these understandings, "transandrophobia" is an unhelpful and counterintuitive idea, as it asserts that there is a unique form of discrimination levyed against men, which is a distinctly anti-feminist idea.
People who push back against this are generally not trying to deny the countless ways that trans men are discriminated against, rather, the misunderstanding of feminist ideas that allows "transandrophobia" to exist is something that allows people to shout down trans women trying to talk about our own oppression; it's a shallow desire to claim "transmisogyny for boys" which is, again, anti-feminist.
Some of what you're seeing is likely part of that debate - feminists discussing the ways in which feminist ideas are misinterpreted.
I'm curious to know where and how you got the idea that transphobia to trans men is something marked as green - i would be rather suspicious of anyone echoing that claim.