Blacks in the USA are one of the poorest demographics. Poverty correlates with violence, crime and homicide. Skin color isn't the most relevant aspect in the black trans debate imo. Its income bracket that is most relevant in determining homicide & crime rates.
I wanting a leftist to bite the bait. But after your post, I don't think too many will. Every transgender awareness day, a lot of people doing these "white supremacy" and "patriarchy" thing and then cited the murder rate of black trans women. To the point, in a lot of mind, that transphobic white men killing black trans women in drove or something. And this is why a lot of leftists don't actually understand intersectionality.
Transphobia does come into play. But not from white community. If this was the murder rate of white trans women, then sure. But minority groups can be extremely religious and conservative in some ways. Black community is not exactly the most welcoming of lgbtq+, especially compare to white Americans. Which often meant, the disowning and the rate of homelessness among this group of people. Homelessness does exposed to a lot of violence as well.
Institutional Racism does come to play in term of legacy of segregation. Being born to higher poverty. And poverty, like you said, has high correlation with crime. And the time of jobs that come to play with some of these demographic like prostitution.
And the gender does play a component, because being a trans male would meant more interaction with females (if they identified as straight). Where as trans female interact more with males, particular cis males. Who tend to be more aggressive and more violent.
As I talk to some people, people literally think the cis straight transphobic white men are what killing black trans women in drove. And despite the high rate of murder, since black trans women are but a very very small fraction of the population. I could easy take one year, charted out all the murders, and look into each specific incidents. I don't remember which year I took. But most of them got murdered by black men. Usually either due to domestic violent, robbery went wrong, or violent due to profession like prostitutions.
A nice thing about intersectionality would be, if you want to solve for something like the murder rate of black trans women. In which every articles love to point out at a certain time of the year. You have to dissect it and proposed solutions to this. Like addressing the homophobia/transphobia within the black community. Improved homelessness aid in these neighborhood. Improve some sort of job assistant training and program so people have options. Or even addressing the domestic violent of lgbt relationships.
People have these simple solution of teaching cis straight white males not to be racist transphobic. And I am sure it help in other cases. But not for this particular problem. What even more annoying to me is that they point out these murder rate, and then call for solutions for other stuffs like trans athlete right or something. Which can totally be discuss. But the profile of these people who got murder, none of them are some privileged athlete competition at the highest level in some university.