A. If 8A and 8b are anagrams of each other, they don't seems to fit.
I am assuming that 8A is a synonym of Opponent.
8 Opponent to 15A without other 9s, not stopping (10; 10)
B. 4A 4 Clue for crows to give punishment to schoolboy solver at
temple (all old) kept by revolutionary and/or significant
figure’s death? (1,7,5; 3,3,2,2,3)
8A & 8B are not anagrams of each other
you are ok with antagonist for opponent synonym 8B is transience - the anagrams of these are at A23d + A 3d
transience anagram - nectar ines to be placed at B20d and B23d
8A Not opponent. Play even higher card. What is the suit of high cards called?
8B Name of a flower that is not an anagram of 8A. Theses are 9- letter words not 10
4A What an errant schoolkid has to write on a black board