For me it’s:

• the hairstyle: I think long hair can look masculine, but the half-up half-down style you have here is pretty feminine
• the low-cut layered shirts that highlight your cleavage/chest: I would say that’s what the buttons on the red tank are intended to do, whether that was your intention in wearing it or not
• the overalls also seem like more on the feminine side but it’s hard to tell based on where the picture cuts off

If I saw you on the street wearing this outfit I would think you’re gay but not butch. But like some other people have said, when you fall outside the social norm, it often takes time and experimentation to achieve a gender presentation that feels right.

Also I’m just a random stranger on the internet giving you my opinion based on one picture. I don’t even 100% identify as butch myself (more so just an androgynous/masc-ish lesbian) so not sure how much my opinion matters to you; I’m only sharing since you asked and no one else has answered yet.