I am a US citizen living with my Mexican wife in Mexico. We have no plans to live in the US, but much of my work is there. We would like to be able to legally work together in US, but work visas appear to be for specific jobs or for emigrating to US. Which type visa would be appropriate to allow us to work together on projects in US and allow us to remain in Mexico?
There's no such visa. She can get a green card as your wife, but that requires actually moving to the US. There's no other immigration benefit your citizenship can get her.