i still don't understand why would anybody even search this term in first place!
all the wallets that i have seed are already supporting QR codes, specially if you are building a cold storage like a paper wallet and want to print your private keys they already do that for you.
additionally if it is general things you want to turn into a QR code like your transaction or your address,  then searching QR code generator would suffice although still not a good idea to use them.