Not really a reliable way. An authentic VTC5A at a factory charge (generally 3.4 to 3.7v for shipping and storage purposes) just won't have the oomph to test to begin with. After about nominal gentle 5 recharge and discharge cycles will be at its most powerful ability after a 6th recharge. Then you do a full discharge in one cycle after hooking the battery up to a multi-meter, placed in a safe testing bin, and discharged fully down to about 2.5ish to 2.6ish volts, also need a temp diode connected to make sure the battery isn't going over 80 to 120C in temp.
An authentic should reach about 80C during the test at its full CDR and never creep above that, the test that Mooch does I believe is about 5 to 10 second on, 30 seconds rest at off, but the battery should be handling a 25amp load no problem, starts reaching 90 to 100C at 25amps it will be a standard VTC5, battery goes over 120C you'll have problem with venting and internal damage, it sky rockets toward 200C + you have a thermal runaway.
Just noticed you are from the middle east in Kuwait, I am sorry but I know of no good online vendors from that region for shipping.
Visual inspection, an authentic Sony should be an almost slightly, metalic sheen pine green on its wrap, not dull or to metalic like on a car paint job, the SE US18650VTC5A then the batch number underneath that and the reversed UR logo should be seen under the wrap in a kind of dull print and if you remove the wrap should be solid and a lot of inking, the insulator ring at the top should be white, not black or silver, positive post should have 3 prongs leading to the top cap, not 4 or 5. I'd start inspection at the prongs, then the insulator ring, then the wrap color, and finally the model and batch number printing. A fully charged VTC5A should also hit like the old VTC3 as it has a very comparable pulse discharge compared to its older brother the VTC5 and the old VTC4 with very little voltage sag when under load. If you don't trust your B&M vendor I wouldn't trust buying any batteries at all from them, and suggest getting a raport and dialogue going with them as a regular customer to get a feel for their morales and business mindset if you are that paranoid about them.