No. The privacy policy states it flatly: your personal data is not sold.
The more useful question is who sees it, and that has a specific answer rather than a reassuring one.
Who sees it
Sellers you buy from. Your name, mobile number and delivery address — so they can deliver. Nothing about what else you have bought, and nothing about other stores. Who can see my delivery address?
Other users see only your public profile: your name, username and photos, and whatever you post publicly. Including, during an auction, that you are the top bidder. Can I bid without my name showing?
The services that run Metzee, each named in the privacy policy rather than described vaguely: the database and sign-in provider, the payments provider, the live-video provider, the messaging and email providers, and the host. They may use it only to provide their service.
Government authorities, where the law requires it.
Selling versus sharing, honestly
A company can truthfully say it does not sell data while handing it to a dozen advertising networks, because "sell" has a narrow meaning. So the sentence alone is worth little, and the list above is what matters.
What is on that list is processors — companies doing a job Metzee needs doing, bound to that job. What is not on it is anybody buying data to target you, because there is nobody.
Why the business does not need to
Metzee makes money on a commission when something sells. That is the whole model, and it is published. A marketplace earning on transactions has no reason to be in the data business — the incentives point the same way as your interests here, which is not true everywhere. How we make money
What you can control
Your notifications, in Settings.
Your public profile — the name shown is yours to set. How to change your name
Your account, which you can delete yourself. Personal details go; the order and tax records stay without you. How to delete your account
If you want the formal version
The privacy policy is the binding text, and it is short and specific on purpose. This page is the plain-words version; where they differ, the policy is the one that counts.
More: can I get a copy of my data, who can see my delivery address, what happens to my data if Metzee shuts down.