My Life In Isekai Multiverse

Let's see.......

A hapless guy was returning home after failing in his 100th job interview. On his way back he got hit by truck-kun and got isekai'd in a sword & magic world. But he wasn't the hero or an aristocrat. But he is reincarnated as a lowly commoner in this feudal medieval world.
Soon he realizes this new world is a mix of Isekai Anime & games.
He took advantage of the situation and he finally found a job i a certain newly emerging kingdom.
Thus, our protagonist began his career to conquer the isekai Multivarse, while building his harem.
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[ This is a kingdom building/army/geopolitics/civilization/wars/realistic worldbuilding novel ]

The premise of this story is in the title. Sorry but can't think any better synopsis then this, I'll fix it later. This fantasy is colossal. The ultimate crossover of fantasy world.Every single anime below are in story. Now the world's involved are,

Overlord
Re:Zero − Starting Life in Another World
Fairly tail
The Rising Of The Shield Hero
KonoSuba
Demon Slayer
That Time I Got Reincarnated As A Slime
Genshin Impact
Black clover
Is It Wrong to Try to Pick Up Girls in a Dungeon?
Goblin Slayer
Mushoku Tensei Jobless Reincarnation
My Next Life as a Villainess: All Routes Lead to Doom!
In Another World With My Smartphone
Log Horizon
The Ambition of Oda Nobuna
Arifureta
No Game No Life
The Familiar of Zero
Realist hero
Cautious Hero
I'm the Villainess
Record of Grancrest War
Otome game sekai
Death March to the Parallel World Rhapsody
Wise Man's Grandchild
So I'm a Spider, So What?
How NOT to Summon a Demon Lord
Tales of Zestiria the X
Akame ga Kill!
Mairimashita! Iruma-kun
The Genius Prince
Maoyuu Maou Yuusha
Spice and wolf
Tsukimichi -Moonlit Fantasy-
CHOYOYU!: High School Prodigies
Kemono Michi: Rise Up
The 8th son
The Master of Ragnarok
Harem in the Labyrinth
The Saint's Magic Power is Omnipotent
Dr. stone