Try to catch Vivian off-guard. Remember that she has no way to escape, so if you catch her before she can lock onto you, you have the head start in damage - and for Moji, that usually means the kill.

Chronos. There is rarely a reason to get anything else for Jenos except Chronos if you're intending to heal with him. If you find yourself being hard-countered get Chronos II then buy another item to properly defend yourself.

Sha Lin is the ultimate way of telling you to get out of the sky - and when you're on the ground, Impaler Arrow is a huge threat for you. Resilience will be necessary; a good Sha Lin will deal too much damage for Haven to be effective.

Recently, Maeve's Midnight was heavily nerfed - it can be countered by Resilience (at the time of making this) and go down to a minimum duration of around 2 seconds. If the option is available to you, buy Resilience - especially if you're her target.