I'm moving from Eloqua and I want to tag some of my leads as sent email so they don't get the email again in the nurture stream. Is there a flow step I can use to say that this lead has already received this email?
No, there is not. Marketo will only recognize that the lead received the same asset if it was sent from Marketo. It must also be the same Asset ID.
What you can do is move those people to a different Stream with new emails.
Kelley you could use a program and smart campaign within the stream. You could add the Not Was Sent Email filter to exclude anyone who received the email outside of the Engagement Program.
Since I've built the same email in Marketo there's no way to say this lead got this email? Just referencing where it is placed in Marketo?
Oh sorry I misunderstood that you sent the email from Eloqua initially and then rebuilt it in Marketo. As Josh said, your bet would be to add them to a SFDC campaign to exclude them.
We don't have "sent" as a status in SFDC. So my workaround conclusion is we created default programs for those streams and tagged them there and removed the email in the stream for the default program as a workaround.