Okay so it’s a ton but try to list as many as you can…
AP Chemistry
AP Biology
AP US History
AP U.S. Government & Politics
AP World History
AP Comparative Government & Politics
AP Human Geography
AP Physics 1
AP Physics 2
AP Physics C: Electricity & Magnetism
AP Psychics C: Mechanics
AP Macroeconomics
AP Microeconomics
AP English Lang
AP English Lit
AP Computer Science A
AP Calc AB
AP Calc BC
AP Stats
AP Latin
AP German
AP Spanish Language
AP French
Like this has never been asked before 
All AP’s are not equal difficulty, and the teachers can make or break the class. If they pile on busywork that doesn’t teach the concepts or prepare for the exam, they are wasting everyone’s time. However, only the students at your school can provide info on that. Additionally, some students obviously find STEM subjects easier, and others find humanities easier.
Some AP’s are intrinsically more time consuming than others. From my experience:
The hardest and/or most-time consuming, IMO, are: Calc BC (if taught as a one-year course after pre-calc), Physics C E&M
A small step down to the next level: Physics C Mech, Bio, Chem
A small step down to the next level: Eng Lit, Eng Lang, USH, Spanish Lit
A small step down to the next level: World Hist, Euro Hist, Art Hist, Calc AB, Calc BC (if taught as a one-year class after Calc AB)
A huge leap down to the next level: everything else
Ok, so first of all, it totally depends on your teacher. But, I’ll rank them for how they most often are. I’ll give each one a score of 1-10, with 1 being easiest and 10 being the hardest.
AP Physics C: Electricity and Magnetism - 10
AP Calc BC - 10
AP Physics C: Mechanics - 9.5
AP US History - 9.5
AP Chemistry - 9
AP Computer Science A - 9
AP Biology - 8
AP Physics 1 - 8
AP Physics 2 - 8
AP Calc AB - 7.5
AP English Lit - 7
AP English Lang - 7
AP World History - 7
AP Spanish Language - 7
AP Latin 6.5
AP German - 6.5
AP French - 6.5
AP Stats - 5
AP Comparative Gov - 4.5
AP US Gov - 3
AP Macroeconomics - 2.5
AP Microeconomics - 2.5
AP Human Geography - 1
OP wants to self study for AP courses that are not offered by HS, in order to impress Stanford/Caltech/Berkeley.