Married to a French man

That's correct.
It's not necessarily faster if she goes back to Brazil .But that's your call.
I volunteer with Les Amoureux au Ban Public,a NGO helping mixed couples with the paper work,and we usually recommend that people stay in France when it's possible. But it's up to you to see what's best in your situation 😊

Thanks for replying!

We are a bit in doubt about what to do, as the most important thing for us right now is that she is able to work.

It seems like we will opt for her to go to Brazil as this will enable her to have the long term stay visa (reunification familial). Do you know if this visa will give her the right to work?

Best regards!!

When you're married to a French citizen it's not regroupement familial.  That is a whole different procedure,nothing to do with you. You,or rather your spouse,will be asking for a visa de long sejour. A category D visa. She'll need to apply for her carte de sejour within 2 months of her arrival in France. This will take about 2 months to get. But she'll be able to work once the carte de sejour application is filed. The récépissé de demande de titre de séjour gives the right to work.
But as you see,you won't necessarily gain a lot of time. It depends on how fast she gets the visa.
Feel free to contact your closest Amoureux au Ban Public,or send a mail to one of our local groups,if you need help with anything.

Her visa from Brazil, as a spouse of French national, will give her the right to work.

If you are married, you just can come on a tourist visa.. take care of all the paper work when you get to france.. no big deal

To immigrate to France from USA per the marriage route, will they want proof of husband's income (he's the citizen) and to inspect living conditions? A few articles said that, but I can't confirm it.