Guys don't you know whether all this projects are erc20 or with their own blockchain?
I don't believe any of them have their own blockchain, but not all of them are ERC20. There is also QRC20 as is the case with Medibloc.
Oh, I see, I'm just not that long in crypto

are there any advantages of QRC over ERC?
ERC is ethereum-based and runs on the ethereum network and QRC is QTUM-based and runs on the QTUM network.
I'm sure you know about ETH, but maybe QTUM is new to you. Check out this article to learn a little more: