L-2 spouses are employment-authorized incident to status, so immigration law permits her to work. Nursing is separately regulated by each state, so she would need the relevant state licence before practising, and that is a professional question rather than an immigration one.
Immigration permission is the easy half
The L-2 classification gives a spouse work authorization by virtue of the status itself, and an admission record showing the proper spousal classification can serve as evidence of it, so she does not depend on a separate employment-authorization application before accepting a job. The limits she faces come from professional regulation. A licensed practical nurse cannot practise in a U.S. state without that state's licence, and the requirements and processing times vary. If she intends to work in a hospital or care facility, she should start the state-board process well before the move. If instead she wants to work in a non-licensed role during the two seasons, L-2 permits that too. Children in L-2 status may study but not work, and lose derivative status at twenty-one or on marriage.
Hypothetical example: the technologist's spouse is a pharmacy technician who hopes to work at a U.S. clinic soon after arrival. Her admission classification may permit employment, but the clinic and state board will decide whether her education, examination history and registration meet the local professional rules. The first review should create two tracks: immigration evidence for the spouse and licensing evidence for the intended occupation. Keep the principal's approval notice, the spouse's admission record and marriage certificate together; keep board correspondence and credential records separately. A common error is accepting a clinic start date before the state registration is issued. Children need their own entry records and school plans, and they cannot treat a parent's work authorization as permission to take a job.