We don’t, we refer to Jira data over its' id. In particular, we don’t store details about users (such as their emails or names) and we don’t store details of issues (such as their summary, description, status, etc.)
Where does OKR for Jira store the data?
OKR for Jira stores data in Atlas Mongo hosted by Amazon Web Services infrastructure in both United States and in EU servers. OKR for Jira data residency is dependant on where your Jira is hosted.