While looking for some Alex replacement I stumbled upon those portraits, sadly it looks as the author abandoned the project as that post was made 2 years ago, and there doesn't seem to be any mention of it as of yet. I tried to make matching sprites and mod the portrait into the game, but after scaling it down the result is not as great as I had hoped. [/IMG] So I was wondering if someone more skilled than me would be able to look less blurry, though I would not call them good, I'll throw in my attempt at matching sprites for the portraits.
When you're resizing pixel art like this, you want to do "nearest neighbor" resizing, and not the default one your program of choice is trying to use. That will solve your particular blurriness issue. However, since you have the full sheet, you can just use Portraiture. Won't fix the .jpg artifacts, but it will be usable just how you have it.