Ender 3 PRO BLTouch V2 perfect on center with small prints but fails on corners or big prints
Following Nathan's answer, I've solved my problem with Nathan's suggestions and the method in  this video.
What I did?

Flashed Creality's original BLTouch firmware to printer
Heated up bed to 60 °C
Leveled bed the old fashion way first, but with slight resistance (you don't have to level perfectly)
Followed the youtube method to find proper Z offset
Opened Cura, Settings-&gt;Printer-&gt;Manage Printers: and added G29; ABL after G28


Voilâ, now your printer prints perfectly! Enjoying the relieving after 1 week of struggling.