[1][2] The PMI guide Requirements Management: A Practical Guide recommends that a requirements tool should be identified at the beginning of the project, as [requirements] traceability can get complex and that switching tool mid-term could present a challenge.
[3] According to ISO/IEC TR 24766:2009,[4] six major tool capabilities exist: Note that INCOSE and Project Performance International (PPI) maintain an official database of tools, the Systems Engineering Tools Database (SETDB).
(https://www.Reqops.com) Note that compliance with, for example, safety standards such as ISO 26262 is supported by few tools directly or indirectly via specialist consulting.
[6][7] Unlike the major six tool capabilities (see above), the following categories are introduced for the list, which correlate closer with the product marketing or summarizes capabilities, such as requirements management (including the elicitation, analysis and specification parts) and test management (meaning verification & validation capabilities).
Specialties, such as OSLC-support, are not presented in the current list, but exist for some tools.