Can Marketo match leads by email instead of Salesforce ID when syncing from Salesforce?

Nambi

We have two systems, Salesforce and Marketo, which are synced.
In Marketo, records are synced to Salesforce based on the email address.
In Salesforce, records created from Marketo are matched using the Salesforce ID.
We do not have duplicate management enabled in Salesforce.
We want Marketo to check the email address instead of the Salesforce ID when creating or updating leads.
The process should start with a Marketo landing page or form submission.
If the email does not exist in Salesforce, a new Lead should be created.
If the email already exists, the existing Salesforce Lead should be updated.
Additionally, when a lead comes from Salesforce to Marketo, Marketo matches it using the Salesforce ID instead of the email address.
Is there any solution or configuration that allows Marketo to match leads based on the email address rather than the Salesforce ID when syncing from Salesforce?

SanfordWhiteman

As with any cross-system sync, a unique identifier is used to maintain the relationship. You cannot use the email address as the persistent identifier of the record across the two systems. That’s simply impossible, since the email address could change on either side at any time.

We want Marketo to check the email address instead of the Salesforce ID when creating or updating leads.
The process should start with a Marketo landing page or form submission.

What do you mean by “start with a Marketo landing page”? Visiting a page anonymously doesn’t perform a lead lookup. And a form submission on an anonymous pageview doesn’t use the SFDC ID to do its lead lookup (how could it?). It already uses the Email Address. So this kind of seems irrelevant to your question about SFDC.