Not sure if this is possible but it was something that I could do previously in Password Depot before I migrated to 1Password so thought I would throw up a discussion and see.
On websites that have more than 2 standard username and password fields for login is it possible to do a custom login sequence? I can find I can add an extra field to the saved Login within 1Password but I am not sure where to assign them to a certain field on the page.
Password Depot used to do it by custom key sequence e.g.
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