I have heard about the polyneix exchange before but don’t have any knowledge about it. But I think with regards to what you stated in the last question, depositing fiat into the exchange. I think it is the same to all the exchange platforms I know, you can rather use your fiat to buy a crypto asset and hold in your wallet, that is if only you want to deposit the fiat. Apart from that I don’t think you can deposit fiat directly to your exchange account.

Anyway, thanks for sharing and you have explained into details about the polyneix exchange. Good luck.