Usually the card itself and border fade before the black ink, though. Here are some cards of mine in various degrees of sun-fading.
At first I thought it might have to do with low on black ink, but then it would actually be grey instead of black, instead of thinner font.
I have some cards which were low on black ink, like these EX Holon Phantoms grey prints I own at the bottom (sorry for the bad picture, the only one I could find right now).
And some other pictures:
The grey Surfing Pikachu at the top here (not mine unfortunately):
Or this Dark Gyarados from the Team Rocket set as well (also not mine):
Maybe cards by default are printed twice, and it only happened once with your cards? I do know some cards where the black is thicker than normal because they printed it an additional time, like these Base Set 2 cards I own myself:
And also those where the black parts are misaligned with the rest of the card (not mine again):
Anyway, color differences happen pretty often, although I must say your cards do look kinda extreme. I’m unfortunately unable whether they are real or fake. If they are fake, they are done very well. But I have the feeling they are real and something went wrong during the printing process.
I actually have some very comparable cards in Yu-Gi-Oh, where the font and thickness of the font also doesn’t match every other card released and look rather weird. Those I know for fact they are real though, since I’ve pulled them myself from a legit deck. I currently don’t have pictures of those Yu-Gi-Oh cards, but might post them later on to show. Although they are non-Holo, the weird difference of the text which almost looks like a different font is very similar as your cards, and also very noticeable every time I look at those cards.
So although it’s still possible they are fake. I’m by no mean an expert in determining real vs fake and can only identify the obvious fake-indicators. But it’s plausible they are indeed real, and something weird happened during the printing process.
Greetz,
Quuador