When Lex is attacking you, try to keep your Illusions between you and him. None of his basic abilities can shoot through multiple targets, his In Pursuit will be forced to target your Illusion instead of you, and you'll receive constant healing.
Your weapon attacks are very precise and deal a surprisingly large amount of damage. Barring if he's being healed, if you focus your attacks on Drogoz, you should be able to take him down within a single clip.
Despite the obvious counterplay, don't use your ult exclusively to counter Makoa ult. He can simply wait for you to die to use his ult, and you can charge yours significantly faster than Makoa can charge his anyway.