Tip overview

As @mcdude said. Save your reversal untill she had used her pounce. After that try to get as close as possible to get a punch on her. A decent amount of maeve players freak and use pounce to get some cover before going out again. Chase her.

Try to predict the spit-salvo combo coming, and use your vine to quickly escape. People often forget that, as Grover, you can vine onto champions as well. A good place to find yourself when playing VS Drogoz is either behind walls or next to your DPS

Try to put your illusions where the enemy team can't see them!

Lex has more health than you. He has more damage and shoots faster than you. He has more combat-ready mobility to chase you down. His ult is suitable for duels. To beat a Lex shows how much more skilled than him you are. Good luck.

Try to use your double jump (or triple jump) as frequently as possible. And try to jump from the left to right, this will confuse your enemies.