How to quickly deploy systems for multiple tx2 using SD card ?

we are wording on Jekpack 3.2.

By quickly deploying are you asking if flash can occur via SD card? Are you asking how to use an SD card on a PC host to flash multiple Jetson? More information on your use-case would help.

Flashing Tegra Device occur via SD card

Directly flashing from SD card is not supported. There are some tricks you can employ if you just want to install a new rootfs and the rest of the system is compatible without changes to device tree or boot environment. There is no possibility to do an actual flash without a separate host PC and the micro-B USB cable.

More information on your situation may help to find an acceptable solution. Knowing if there is some subset of the environment you want to flash instead of an entire release would be an example. Without significant details there is no way to suggest a workaround.