Increasing cohesion could theoretically reduce coupling in a system, but it won't in all cases.
These two quantities are not exact opposites as some imagine. For example, Patel et al say, "Information hiding seeks to minimize connections (coupling) between two different components while cohesion seeks to maximize connections within a component." [Sukesh Patel, William Chu, Rich Baxter, "A Measure for Composite Module Cohesion", ICSE '92: Proceedings of the 14th international conference on Software engineering, June 1992, pp 38–48, https://doi.org/10.1145/143062.143086]. This is incorrect, as it should never be a goal of software engineering to maximize coupling at any level!
Taken one step further, this leads to confused statements such as the following: "High cohesion with low coupling appear to be competing goals." [James M. Bieman, Byung-Kyoo Kang, "Measuring Design-level Cohesion", IEEE Trans. Software Engineering, 24(2):111-124, February 1998.]
If cohesion is properly understood as the singleness of purpose of a unit of software, then moving related pieces of code nearer to each other should increase cohesion, and may or may not reduce coupling. So these two quantities are not opposites, and they are not completely orthogonal either. This is what makes them confusing.