Well, generally people who pick Scout for farming prefer Bullet Marker or SR + Thauma + X class (pick one classe that will have a good AoE or make your skills stronger).
But since you want to farm with an assassin, >>> I <<< would go for Assassin - Outlaw - Linker, but I need to say that you will lose the mobility of a SR and the buffs from Thauma.
Corsair is also a good class, but in this case >>> I <<< think linker will be the best option.
I’ve never tested ardigo or rangda to be honest. Maybe they end up being a good combination for your character. But again, >>> I <<< would recommend the build that I passed.
If you don’t know anything about skills, >>> I <<< suggest:
https://tos.neet.tv/skill-planner#51239.154555.1f253f415465.1f243a556675.253f4a8a55
NOTES: I AM NOT A SCOUT USER AND I PLAY 100% FORFUN. It’s how I’d build my own char. So feel free to search more combinations, builds and how they connect.