Azorius Control runs almost entirely blue and white spells, so Mystical Dispute counters Teferi, Hero of Dominaria, Memory Deluge, No More Lies, or Supreme Verdict for as little as {U}. Volcanic Spite and Spell Snare are nearly dead since this opponent fields very few creatures, and Supreme Verdict can't be countered anyway so removal is mostly wasted. Negate backs up the plan against The Wandering Emperor and their countermagic suite. Prioritize protecting your own threats and planeswalkers with countermagic rather than relying on removal, since this matchup is won by resolving and protecting a late-game bomb like Atraxa, Grand Unifier or The Theorist, Jace Beleren.