Can we update the value in any lead field using Velocity script?
This is not possible with the current features.
What you can do is use a webhook to send the lead info to some code, do the processing/transformation and then map the response to lead fields. You would need the ability to host a script to send the lead info to, but other than that it's usually feasible for most users.
If you don't have the staff to host the script, there's a tool called FlowBoost that should be able to do this
Create a Webhook - Marketo Docs - Product Documentation
You are a true rock star. Thanks for helping me with your valuable knowledge.
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