holehe
Check if the mail is used on different sites
...It supports more than a hundred websites and is commonly used during reconnaissance, digital investigations, and account exposure assessments. holehe is designed to operate quickly and quietly, emphasizing efficiency and minimal footprint during enumeration tasks. The project can be used both as a standalone command-line tool and as a library embedded into larger automation pipelines. Overall, holehe provides investigators with a focused and scalable method for mapping an email’s online presence.