How do I go about this?

I was on PeoplePerHour and sent a proposal to someone looking for a translation job, I didn't get it , but the guy that had initially posted the job approached me about doing something else.

He basically stated that he was a senior web developer and wanted to use an account under my name on a different platform. Apparently, he can make at least $3000 a month and compensate me with 10% of all earnings.

I'm just starting out on trying to make some income online, and this situation does raise a few flags and I'm not entirely sure how to respond, but I don't want to be rash.

If the post is inappropriate, I'll happily take it down. I just figured this would be a good place to get some help.

Thank you.

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