You only need to be an extrovert to be confident.
The direction of intergration is towards more E, not towards more J.
You say INTP shadow is ENTJ?
Then INFP shadow is ENFJ?
you don't become your shadow when you get healthy, you become more confident. This is especially true for fours and fives.
INTP (5) should learn to become carefree and confident like ESTP (8, 7w8). Like turning your thoughts into action rather than dwelling on introversion and worry about the consequences. This is the direction of growth.
Just like INFP (4) should learn to become more bold and thickskined like ESFP (7, 9).
The fear of poverty turns people into slaves of money.
"In this Caesar there are many Mariuses"~Sulla
Conquer your inner demons first before you conquer the world.