Too good. Seriously, that's the problem: she looks too good.
In the live-action adaptation, Jenna Coleman's Constantine is rocking a chic creamy trench coat and sports a look that generally channels a vibe of someone who is pretty wealthy. Despite her not being a straight-away gender swap, Johanna has still inherited a lot from John Constantine – except for his "worn out" look. While John would sometimes look like he's literally been through hell (which is occasionally true), Coleman's character can easily be mistaken for a social media influencer, not an exorcist tormented by her past mistakes.
Some fans took issue with that, suggesting that Johanna's look should have been less polished to make her seem closer to what some called "a working-class magician". However, others immediately argued that there are several reasons for it not to be a thing.
First of all, 'The Sandman' hints at the fact that Johanna is familiar with the royals: her exorcising gig with the princess and a footballer possessed by a demon does not seem to be her first encounter with royal family. Hence she might have landed decent payments for her job, which is something she might as well invest in her looks – simply because she can.
Secondly, as she remains an independent character and not a John Constantine rip-off, she is not obliged to strictly follow his fashion choices – despite the fact that her outfit is clearly homage to Hellblazer's classic look.
And even if one still chooses to perceive her as a female version of John, there is an explanation for why her fashion choices differ.
"Think of Joanna less as, "John, but female", and more of as "What if John grew up female?" Even having the same experiences, they're filtered through a female world view, and reacted to as such." – /Kris_Winters
'The Sandman' is currently streaming on Netflix, with Jenna Coleman appearing both as modern-time Johanna, and Lady Johanna Constantine from the past – the ancestor of Hellblazer.