An L-2 spouse is employment-authorized incident to status, so he may work, including self-employment, once admitted. Whether serving Canadian clients from a U.S. address raises tax or professional-licensing questions is separate from immigration permission.
L-2 work authorization is broad; the other questions are not immigration
Spouses of L-1 principals are authorized to work by virtue of their status, and the admission record itself serves as evidence of that authorization, so he does not need to wait for a separate employment document before taking work. Self-employment is included; nothing in the classification limits an L-2 spouse to a payroll job. That settles the immigration side of running an accounting practice from a U.S. home. What it does not settle is whether an Ontario-designated accountant may hold himself out to Canadian clients while resident in another country, how the income is taxed on each side, and whether any U.S. state where he serves clients regulates the work. Those questions belong to his professional regulator and a cross-border tax adviser. Children in L-2 status may study but may not work, and their derivative status ends at twenty-one.
Hypothetical example: the manager's husband plans to offer bookkeeping to several U.S. restaurants from their apartment after receiving L-2 admission. The first review should separate his work authorization from business, tax and licensing decisions. His valid admission record is the immigration document a payroll employer will examine, while a client contract, tax registration and any accountancy-regulator guidance govern the practice itself. Children have a different analysis: school enrolment may be allowed, but derivative status has an age and marriage limit. A common mistake is to treat the whole household as one employment case. Make a family table listing each person's travel document, relationship evidence, intended activity and independent deadline so a spouse's business plan does not obscure a child's approaching status change.