NNGroup describe User Research Repositories as follows:
Research repositories store and organize information about UX research. They collect not only methodology-related documents, but also research results at various levels of granularity (from individual findings to reports). Their purpose is to streamline the work of the research team and also to make research widely available and easy to consume throughout the organization.
We are currently trialing Notion.so as a research repository, but we don't yet have enough experience to advise if they are the right fit for your company. Our hope is that it helps our team access the research outcomes more easly, which will enable them to make better decisions during product development.