How do we know when a wallet is sandbox compatible?

The Chinese tech giant Cheetah Mobile has announced this week it just launched a new multi-cryptocurrency wallet that stores bitcoin core (BTC) and ethereum (ETH). The firm’s ‘Safewallet’ features a three-tiered security defense system with an intuitive interface.

Where is the digital yuan and digital dollar?  

These wallets hold your secret keys, used only when you enter the pass code on your handheld. Damn close to a sandbox wallet, how do we add digital bearer fiat simply?

Escrow router and no double spending.  The escrow router is the uncongested, ringed fence that can move bearer assets between pits and ledgers, securely. 
No double spending means what it means. So, any wallet can do a point to point exchange between trusted parties, except all parties pre-qualified for trust.  I can give you an escrow instruction, denominated as ten bucks, a promise by the escrow router to swap between my fiat account and your fiat account. Submit these escrow instructions at your leisure, the money is safe. 

Simple rules, simple escrow router to create. But it requires counterfeit proofing.  We know how to do that, and biometrics makes the current system quite safe. Fiat bankers could accept the reality, create special accounts managed by escrow routers, and hold the digits at zero interest. Fraud is minimized by account limits to insecure clients. Much safer then 'card-not-present- policing. And fiat bankers could easily charge a half point, at zero  risk, a bearer cash fee.

Fiat bankers worst case scenario.  Robotic cash is already in wide use and fiaters are clueless! They would not know the velocity of their accounts when escrow optimizers and sandbox clearing houses close the internal loops. The issue will be resolved very soon, it is kind of a real threat. Right now the money launderers have the Equifax database and are using that to  set up robotic account, informally.