The short answer
Swops has no setting to change the address you sign in with. There is no password either: your email address is your account. Account›Your account shows it as Signed in as your address.
Signing in with a different address creates a separate, new account, with its own empty personal space. Nothing moves across to it by itself.
What to do depends on why you need the change.
Only the email on your QR card?
If you want people to see a different address, you do not need a new account. The details you share come from My card, which you can edit freely: open My card and tap Edit. The instant follow-up email uses those details too. See Edit or delete My card.
A new work address, in a company workspace
The contacts in a company workspace belong to the workspace, not to your account. So:
Ask the workspace owner to invite your new address. If the team is full, the owner can remove your old account first.
Sign in with the new address and accept the invitation. You see the same shared collections and contacts. See Join a team.
Leave the workspace with your old account, or ask the owner to remove it. That frees its seat. The contacts you captured stay with the team.
Do you own the workspace? Ownership stays with the account that created it. Contact us with your current address before you stop using it.
Your personal space
Personal collections cannot move to another account, and Swops has no import. Before you switch, export them to keep a copy for your records or your CRM. See Export contacts to a CSV file.
A paid Solo plan, or anything else
Contact us with your current address and tell us the new one. We will tell you what can be done.
Swops can only send sign-in codes to the address on the account. If you are about to lose it, for example when you leave a company, export what you need and sort out your workspaces first, while you can still sign in.