12Peter213
The Duress pin and or password has so much lower demands compared to Logins, lockscreens, encryption keys etc. The only thing to always consider when picking a duress pin is, will this be triggered by mistake?
I would not create a Duress pin '11111', since it would easily get triggered in a pocket, but '12345' would not and is therefore a candidate.
I also would avoid say, the real unlock but just altering the first digit, since this would be Pocket-safe, but not 'Yourself-safe', and runs the risk of some stressful day you yourself triggering duress on unlock.
The point is, don't overthink the Duress code, it can be dirt simple since it isn't a real password that locks your device, 'only' a self destruct trigger that should be chosen for not easily butt-triggered while as simple as possible.