No, Sage Advice addresses this

Per Sage Advice:

Question Asker: Hi guys can a fighter use 2 maneuvers - Riposte on enemy's attack & Pushing Attack on his attack? i.e 1/attack

Jeremy Crawford: The intent is no more than 1 maneuver associated with any attack. Riposte is in a gray area, but I would say no.

So no, since the Feinting Attack maneuver is already affecting your attack, you can't use another maneuver on it.

(In the asked case, Riposte triggering gives you an extra attack; that attack is "associated with" the Riposte maneuver, thus you can't use another maneuver on the attack. If that's a gray area that still has the Sage leaning no, then Feint+another maneuver, where you're literally adding both effects and damage dice to the same attack, is a definite no.)

The intent is that you can't apply multiple maneuvers to one roll; Sage Advice addresses this

Per Sage Advice:

Question Asker: Hi guys can a fighter use 2 maneuvers - Riposte on enemy's attack & Pushing Attack on his attack? i.e 1/attack

Jeremy Crawford: The intent is no more than 1 maneuver associated with any attack. Riposte is in a gray area, but I would say no.

So no, since the Feinting Attack maneuver is already affecting your attack, you can't use another maneuver on it.

(In the asked case, Riposte triggering gives you an extra attack; that attack is "associated with" the Riposte maneuver, thus you can't use another maneuver on the attack. If that's a gray area that still has the Sage leaning no, then Feint+another maneuver, where you're literally adding both effects and damage dice to the same attack, is a definite no.)

No, Sage Advice addresses this

Per Sage Advice:

Question Asker: Hi guys can a fighter use 2 maneuvers - Riposte on enemy's attack & Pushing Attack on his attack? i.e 1/attack

Jeremy Crawford: The intent is no more than 1 maneuver associated with any attack. Riposte is in a gray area, but I would say no.

So no, since the Feinting Attack maneuver is already affecting your attack, you can't use another maneuver on it.

No, Sage Advice addresses this

Per Sage Advice:

Question Asker: Hi guys can a fighter use 2 maneuvers - Riposte on enemy's attack & Pushing Attack on his attack? i.e 1/attack

Jeremy Crawford: The intent is no more than 1 maneuver associated with any attack. Riposte is in a gray area, but I would say no.

So no, since the Feinting Attack maneuver is already affecting your attack, you can't use another maneuver on it.

(In the asked case, Riposte triggering gives you an extra attack; that attack is "associated with" the Riposte maneuver, thus you can't use another maneuver on the attack. If that's a gray area that still has the Sage leaning no, then Feint+another maneuver, where you're literally adding both effects and damage dice to the same attack, is a definite no.)