"Impact" tab of an issue displays list of requirements that can be affected if this issue is taken to work. Analysis is carried out based on the similarity of the issue and the requirement texts. Use this information to localize the requirements that have to be analyzed and modified.
Also, use a link between issues and functions and between requirements and functions to identify requirements that will be modified in the case of implementation of some issue. On the function page, you can see links to the requirements that detail it. Open the list of requirements and review their content for potential changes. This technique allows to localize requirements with potential changes without spending a lot of efforts.
Enable the display of incurred workloads to estimate potential workloads for development, testing, and documenting in the case of change implementation.