The first thing I do with a green bag is hold it against the inside of my wrist, where the veins show, because that tells you more than any mirror will. A green that goes grey or muddy against your own skin is a green that'll sit dead on a coat too, no matter how lovely it looked on the stand. I learned this with a bottle green tote I bought because it matched nothing and I thought that made it clever. It matched nothing. There's a difference.
The easiest greens to live with are the ones with a bit of grey or blue folded into them, a sage, a eucalyptus, something closer to the underside of a leaf than the top of it. Those sit next to navy, camel, black, grey, practically anything, the way a good foliage sits in a bunch and never fights the flowers. A sharper green, the acid or the true grass colour, is a brilliant bag but it wants to be the only loud thing happening, so wear it against black or white and let it do its own shouting. Patent or a glossy finish pushes any green younger and punchier, while a soft matte leather in the same shade reads older, calmer, more Tuesday than Saturday. Olive is the one that fools people into thinking it's a neutral, and it nearly is, it just needs warm tones around it or it goes a bit medical.
Where green lets you down is honesty time. If you're someone who buys one bag a year and needs it to go with absolutely everything without thought, a true neutral will serve you better, and I say that through gritted teeth because I'd rather die than reach for beige. A very dark bottle green in low light reads as black anyway, so if you wanted the fun of green and photograph badly in anything but daylight, know that going in. And a textured or structured green bag shows every scuff more than a plain black one does, so it's not the forgiving option for a daily bag that gets kicked about on buses. Fit wise, check the strap drop before anything else, a crossbody that sits too long will swing the bag into your hip with every step, too short and it rides up under your arm and pulls your shoulder forward. A shoulder bag should sit with the top handle not stretched, not slack, and if it gapes open at the top when you lift it, that's the bag telling you it's not built for a phone and keys and a book, it's built for looking at.
Best for anyone who wants one bag to do the colour work while the rest of the outfit stays sensible.