I should also mention alternatives. There are free or open-source image editors like GIMP, Krita, or Photopea that might meet their needs. Portable versions of these could be an option if they're looking for portability.
They might be looking for an offline installer. Adobe does provide offline installers, but users need an active subscription. So if the user has a subscription, they can download it from Creative Cloud. If they don't, that's a problem. adobe photoshop cc 2018 19 portable download 2021
Another angle is if the user is trying to avoid the Creative Cloud activation. Adobe uses a license tied to macOS (if on a Mac) or Windows, so a portable version wouldn't work around that unless it's pirated, which isn't an option I can support. I should also mention alternatives
First, I need to address the legality. Adobe Photoshop is proprietary software, so distributing or using cracked or pirated versions is illegal and unethical. The user might not be aware of the implications, so I should clarify that. They might be looking for an offline installer
There's also the possibility that "19" refers to a version number. Photoshop CC 2018 was version 19.0, so maybe that's where the "19" comes in. But that's just a version name.