You're looking for a feature related to Kenka Banchou 5 on the PSP with an English patch download.
Feature Overview: Kenka Banchou 5 English Patch
Q: Is downloading the pre-patched ISO illegal? A: In most jurisdictions, downloading a copyrighted game you do not own is illegal. However, applying a patch to your own legally dumped UMD is 100% legal. Fan translations exist in a gray area; they are rarely targeted by companies because the game is abandoned (no modern rerelease). Kenka Banchou 5 Psp English Patch Download
Q: Will Spike Chunsoft ever release an official English version? A: Very unlikely. The series is dead in Japan. No Western publisher has touched it since Kenka Banchou: Badass Rumble on PSP (which was a localization of KB4, and it sold poorly).
Q: Can I play this on my PS Vita?
A: Yes. Using Adrenaline (a PSP emulator for Vita hacked with Henkaku), you can copy the patched ISO directly to ux0:pspemu/ISO/. You're looking for a feature related to Kenka
Do not download patches from random file-sharing sites. They are often outdated, riddled with malware, or dead links. Go to the source:
Absolutely. Here is why you should download this patch today: Do not download patches from random file-sharing sites
No. Spike never localized Kenka Banchou 2, 3, 4, or 5. The only official English release in the entire franchise is the first PSP game (retitled Kenka Banchou: Badass Rumble) and a niche PS4/Switch title, Kenka Banchou 6: Soul & Blood, which only saw a digital release in Asia with English subtitles.
Thus, the fan patch is the only way to experience Banchou 5 in English.