1. A method for impact analysis of change requests of a project scope, the method comprising: identifying, by one or more processors, artifacts and tasks that are impacted by a change request on a target project of a project scope, based on a change request repository, an artifact dependency network and a task-artifact mapping repository, wherein the change requests are requirement dependencies and requirement constraints of a plurality of applications for the project scope, wherein identifying the artifacts and the tasks that are impacted by the change request on the target project of the project scope comprises: obtaining, by the one or more processors, requirements, requirement dependencies and requirement constraints of the project scope for identifying the artifacts and tasks that are impacted by a change request on the target project of the project scope; generating, by the one or more processors, a first grouping scheme according to the requirement dependencies, wherein the requirements are divided into one or more groups such that requirements having a dependency are included into a same group; receiving, by the one or more processors, user-defined relationship constraints; generating, by the one or more processors, a set of candidate grouping schemes that satisfy the user-defined relationship constraints based on the first grouping scheme, wherein each candidate grouping scheme in the generated set comprises one or more groups; and calculating, by the one or more processors, a combined indicator for each candidate grouping scheme in the generated set according to the requirement constraints; determining, by the one or more processors, an impact analysis priority for each of the identified tasks based on associations among the change request and the identified artifacts and tasks, and a project status tracking repository; and analyzing, by the one or more processors, an impact of the change request on each of the identified tasks according to the determined impact analysis priority.