Surely most U8g2 examples will just run out of the box.
Please quote which example(s) do not work e.g. example name + constructor statement.
David.
Edit. I just built and ran GraphicsTest_u8g2 with this constructor:
U8G2_SSD1306_128X64_NONAME_1_HW_I2C u8g2(U8G2_R0, /* reset=*/ U8X8_PIN_NONE);