User ID best practices

Hello there,

Just a few questions regarding user ID:

At the moment, I am using Stape’s WP plugin, which pushes user data such customer id into DL for every event WHERE user has already logged in / registered. However, I would like to create / store user_id in a 1p cookie, where I can also use in non-ecommerce events like login etc.

Question1 What are some plugins that could help me generate consistent user_id (ideally hashed email) and save it as 1P cookie?
Usecase=> To pass this to CAPIs

Question2 Can I pass this user_id to stape store so I can retrieve the hashed id later and stitch it with subsequent events WHEN previously identified user comes in after 7 days?
Usecase=> To have complete user journey and give credit to each touchpoint

Thanks!!