The short answer is NO.
The long answer requires a little history lesson.
You cannot play a PS4/PS5 game on a PSP emulator. It is physically and technically impossible. The PSP had 64MB of RAM. The PS5 has 16GB of GDDR6 RAM. The architecture, file systems, and processing power are centuries apart in tech terms. God Of War Ragnarok Ppsspp Highly Compressed BEST - Google
So, if you see a YouTube video or a website claiming: “Download God of War Ragnarok PPSSPP Highly Compressed (50MB)” — it is 100% a scam, a virus, or a fake file.
Sony offers God of War Ragnarök via their PlayStation Plus Premium cloud streaming service. The short answer is NO
Warning: If you download a file labeled "God of War Ragnarok PPSSPP Highly Compressed BEST" from a random forum, you are likely downloading a virus, a survey scam, or a renamed ROM of a different game.
Result: You will have a better-looking game than the original PSP, with upscaled textures and zero lag. You cannot play a PS4/PS5 game on a PSP emulator
Scammers know that God of War Ragnarok is popular. They use SEO tricks to rank for keywords like "God Of War Ragnarok Ppsspp Highly Compressed BEST - Google" to lure you into clicking malicious ad links, survey scams, or downloading malware that will steal your data.
To make old PSP games look like a modern masterpiece (approaching Ragnarok quality):