I talked to cyrio094 about that. He did it before.
He said he bought gold from those money website with his mule account and sent it to his main and still got banned both accounts.
Nexon is strict about these deal. I have no idea how they fount out about his deals. Maybe because of someone named fnjfmsekf" sending you money and is Lv 1 is very obvious? (Yes. Nexon keeps tracks on who sends gold and they have low levels blacklisted on they monitor system on purpose to catch you). So I never buy gold off website. Buy it off people with real accounts. Chances are you'll never get banned.
TL;DR?
Do not buy gold off website with bots, nexon tracks low level sending you gold thru a system log.
Buy it off real people who has a level 40 or higher, chances are you'll never get banned because Nexon will think he helped you out, not traded money for gold/items.
Here's his quote; "got banned only once for goldbuying was on a website. Used a lvl 3 acc to accept the money and then sent it to lvl 72 Vella got both of the accounts banned. "
Then I asked him how it happened he replied.
"Duno tbh, I did buy from a website so they probably DMCA'd the website and got the log of the accounts that bought. Since I only got caught like 6 months later.
Also most of the sites will send you money from low level accs anyways :|. "
So they may not ban you over night. But they'll catch-on.