Darius Supreme by Kotario

The MC was a cutthroat businessman who died of old age, brought by a goddess to a world that seems to be a combination of different cultures. Sword and sorcery, Japanese mythic, mecha, ect. Monsters and fantastic beasts. He is given tasks by the goddess to "entertain" her upon pain of death if he fails, so he tries to do what he can even by risking others' lives to manipulate events to succeed.

The MC is quite smart and crafty. He prefers planning and preparation over fighting. He is quite evil in the sense that genocide is nothing to him in pursuit of his strategic goals, but doesn't mistreat people randomly.

The MC is a mage. The MC has the typical big system cheat, exp to gain levels with a reward of ability and skill points, among other advantages.

The system is definitely not the focus of the story. The MC hardly ever even checks his status, save to add points here and there. The author tries to minimize it, tries to describe combat in a fun way just to avoid the annoying system trope.

The side characters are interesting, the world building is decent, the economy and politics are filled out enough to be immersive and a bit believable.