Are there any exchanges that don't require photo ID, or other personal info, if no fiat currency is involved?
Only crypto in and out.
BitMEX doesn't deal with fiat currency at all, just BTC, so there is no KYC. Deposit BTC --> trade futures or swap contracts (including altcoins) --> withdraw BTC. I'm adamantly against giving my documents to exchanges. After the BTC-e takedown, I am not comfortable dealing with unlicensed exchanges like Bitfinex.