The code of Hentoid relies on the Android framework. It means it depends entirely on your phone's operating system, and cannot run on a desktop JRE. The best chance you have to run it on a computer is to use an Android emulator such as Nox or Bluestacks.
Just to clarify : Hentoid does NOT reprocess / compress any picture when downloading. What you get is exactly the same picture you would get when downloading from any desktop browser.
However, I can understand viewing it through Nox isn't ideal, and the emulation certainly renders a lower quality image than what you would get by viewing it directly on your disk.
A good place to start for a PC "equivalent" would be https://github.com/RipMeApp/ripme
nope, I batched resized them using Photo Editor then I replaced the original images and it lead to lower file size, I am just confused why the app still considers it at that size, I considered putting it in external storage and it showed the updated size. Does it have to do anything with its json file which I can edit?
Have you tried using a vpn? That's what I use when I want to browse sites our coutry blocked (yes, I'm from the ph too) I personally use ProtonVPN. It doesn't have any limited data usage, just a data speed cap, iirc. All for free. You have to create an account tho.