Did they have a plan for Tess??

Tess made sense (more or less) the first season she showed up , but ever since it feels like they loved the actress but had no idea what to do with her so they kind of made her dk everything. It’s tooooo much

1. She was somehow on the island with Oliver
2. She was a secret assassin for checkmate
3. She was trained by granny goodness
4. She’s somehow an ace hacker who can replace chloe as watchtower