Upscayl VS waifu2x

That website? No, I just used upscayl with the Digital Art preset. Source: 10 months ago

Upscayl, I've used it before, it's great. Source: 10 months ago

You can use Upscayl on pc and SuperImage on android to enhance your image so you don't have to find the hd version, both the applications uses you device's gpu to enhance your image. Source: 11 months ago

Might as well just run upscayl locally then. https://github.com/upscayl/upscayl. - Source: Hacker News / 11 months ago

Instead of finding images that are already FullHD, I've found an open source software for image upscaling which seems to work very well with digital art/styles similar to something like Studio Ghibli, which is the style as was going for, so works great for me! Source: 11 months ago

In an effort to restore them as much as I could, I used a combination of waifu2x ("Single-Image Super-Resolution for Anime-Style Art using Deep Convolutional Neural Networks"), Clip Studio Paint resize/cleanup tools, and manual cleanup done by hand. Unfortunately, the red text on the title page was a lost cause. If anyone can decipher solid red rectangles please contact me lol. Source: about 1 year ago

Maybe this would help. There's also an app version of it. Source: about 1 year ago

I would recommend putting it through an upscaler beforehand, it seems a bit small. Source: over 1 year ago

Http://waifu2x.udp.jp/index.html found this image upscaler from https://www.reddit.com/r/FireEmblemHeroes/comments/a51f0k/i_turned_yusuke_kozakis_artwork_into_a_high/?st=JPIZKYIB&sh=f12f76fe a while ago, perhaps that would be the closest if IS doesn't release anything. Source: over 1 year ago

You can make it bigger for print by using by using an Japanese AI image enlarging tool. Source: over 1 year ago