If you are using the modern build, here is how to enable the default widescreen hack:
For nearly two decades, the God of War franchise has defined the action-adventure genre. Before Kratos wielded the Leviathan Axe in the Norse realms, his original rampage through Greece on the PlayStation 2 was a technical marvel. However, returning to these classics— God of War (2005) and God of War II (2007)—on the PCSX2 emulator presents a visual dilemma: these games were designed for the 4:3 (fullscreen) era of CRT televisions. God Of War Widescreen Patch Pcsx2
: If patches don't seem to apply, verify your game's CRC (Cyclic Redundancy Check) code. Modified ISOs or different regional versions may have a different CRC that doesn't match the included patch file. Users on Reddit often discuss how to troubleshoot these patch conflicts. If you are using the modern build, here