Some schools do limited stacking, where merit scholarships first replace unmet need, student loans, and work expectation, but then replace need-based financial aid grants. For example:
https://students.ucsd.edu/finances/financial-aid/types/scholarships/
https://financialaid.stanford.edu/aid/outside/
However, different schools have different policies, and policies may differ for different scholarships at the same school as well.
Remember also that “need” and “meeting need” are based on each school’s definition, which may vary from one school to another (and from what the FAFSA EFC may imply).