Monster Hunter Portable 3rd HD

[LunaMoo]

Well, you do have cheat engine so I imagine you know the basics? Just attach ce to ppsspp running MHp3rdHD(open the process), then make sure you have mem_mapped in scan settings as you saw and click the square near the first entry on a cheat table. That will activate aob scan script to find the psp memory inside ppsspp(because it's not static).
Once it finds it, it'll show a list of options grouped into few entries for readability. Just open Player->Name and it'll have entries to change name by either typing it in as text(if your character was named using full width characters, it'll show initially as "???...") which will result in half width characters or with hex if you do want to use full width characters and know how to use it. It stores name in two places so make sure to edit both(the second one is for the guild card).