Hi, Vaibhav,
Regarding your question to select the processor to control two motor with 12 PWM signals, we have MC56F84xxx for example MC56F84789, it has TWO eFlexPWM modules, each eFlexPWM module can output at least 8 channels PWM signal, so the MC56F84789 can output 16 PWM signals, all the PWM signals support center-aligned or edge aligned, and it supports complementary mode with deadtime insertion for the PWM pair. But the MC56F84xxx odes not support AEC-Q100.
The MC56F82748 supports AEC-Q100, but it has only one eFlexPWM module, can output 8 PWM signals.
I suggest you consider S32K family which support AEC-Q100, it has FTM modules, the FTM can output PWM signals, one FTM module can output at most 8 channels PWM signal.

This is S32K link:
32-bit Automotive General Purpose MCUs | NXP
Regarding the MPC547x, it appears that the processors use TPM to generate PWM signals, I am not familiar with the TPM module, I suggest you post your question to the MPC5xxx community link:
https://community.nxp.com/community/s32/mpc5xxx
Hope it can help you
BR
Xiangjun Rong