I've never encountered a "women + trans" space IRL, only online, and I wouldn't personally use one myself. I think that phrasing is based on the assumption that trans men aren't really men, so I wouldn't want to participate in a group like that. The ideal space for me would be one specifically for gay trans men (by which I mean Homosexual Gay, not Pansexual Gay), because I feel like I don't really relate to straight trans men very well, so a mixed trans group would probably not be that useful to me. In general I think I'm in favour of smaller, more focused/narrow groups, rather than larger catch-all groups.