Yes, you can use 2 4G sim cards in this phone.
Yes, Samsung Galaxy J7 Max does have Ultra Data Saving mode.
Yes, Galaxy J7 Max does have LED Flash for the front camera.
Galaxy J7 Max is make-in-India product from Samsung.
Yes, you can use 2 sims and 1 memory card at a time in Samsung Galaxy J7 Max.
Samsung Galaxy J7 Max is worth considering if updated software and a great camera are your priorities.