Fighter YO-YO counter measure?
Sort of amusing F-16s were used here, instead of older vintage aircraft.  One must realize those little turns would involve high Gs that may incapacitate the pilots.  Also, any "yo-yo" would bleed off a lot of energy and make B an easy target for wingman of A.

One "oldie but goodie" would be for A and its wingman (person) to weave and have B turn right into the wingman's line.  This is the value of teamwork.

However, these days, more realisticly, you need to dodge the opponents missile, which can be very tough.  Stealth and shoot now rule.  But old methods should still be studied.

In the second scenario, one on one, aircraft A would also try to "yo-yo", and they wind up in "a rolling scissors".  The aircraft with more power to weight and better turning rate prevails.  For identical aircraft, it would be pilot skill.  But for modern aircraft with missiles and partners, this type of turning engagement would be very rare.