Systematic and scoping reviews both aim to retrieve a comprehensive set of literature on their topic, so searching one source is not adequate.
Bramer et al. (2017) state that searches for systematic reviews should search at least Embase, MEDLINE, Web of Science, and Google Scholar as a minimum requirement to guarantee adequate and efficient coverage.
Batten, J., & Brackett, A. (2020). Ensuring the rigor in systematic reviews: Part 3, the value of the search. Heart and Lung, 50(2), 220-222. https://doi.org/10.1016/j.hrtlng.2020.08.005
Bramer, W. M., Rethlefsen, M. L., Kleijnen, J., & Franco, O. H. (2017). Optimal database combinations for literature searches in systematic reviews: a prospective exploratory study. Systematic Reviews, 6(1), 245. https://doi.org/10.1186/s13643-017-0644-y
Which databases should I search when doing a systematic review?