@wyansas
1) The 1st edition Asian Samurai SMB: I'm quite sure the seller* swapped out the original PCB, most probably because it got damaged or wouldn't boot. These days there's awareness that Samurai carts are valuable to collectors and unscrupulous sellers will do anything to make a quick buck. SMB carts from all regions are easily available in India and it's not hard to get an NTSC PCB. Would you mind posting a clear picture of the board? Is the lockout chip also for NTSC consoles?
2) The SMB Samurai cart: I would say only 30% of carts with pure Samurai labels have legit Nintendo boards. Most of them have bootlegged boards with windowed ROM chips. Samurai officials claim these are the work of a pirate outfit but I HIGHLY doubt that. I'm pretty sure Samurai themselves bootlegged the boards, with or without Nintendo's knowledge. And I have pretty damning proof: I found a few games with original Nintendo boards fitted with windowed ROM chips! Now where would a pirate outfit get official Nintendo boards from? Pretty sure it was Samurai themselves transitioning from 100% official boards to 100% bootlegs.
3) The Asian-Spanish cart: I have no damn clue . The board has a lockout chip with the code 3196A and that was meant for Asian and Hong Kong versions. Maybe the label was just a weird misprint
* Maybe not your seller but a previous one, basically from the original overseas seller.