According to a quick google search, the log file is located here on Mac (which from your post, it sounds like you are on) 

"User/YOUR_USER_NAME/Library/Application Support/Endless Space 2/Dump Files"

And going here to get tech support issues is generally better since more people who know what they are doing will see it. You might not get a response for a day or two from someone who works at Amplitude because I believe they are all still on break. If you upload the Output.log here, It'd be a start so people can actually look at it and give you help.

oh ok
im using windows on something that used to be a mac, im not on a mac

The output.log should be under Documents/Endless Space 2/Temporary Files then 

its not

Diagnostics - 2020'01'01 @1723'42''.html

output_log.txt

here's output_log i guess? i dont know

Hmm, have you tried validating the game?

You make use of Intel(R) Iris(TM) Pro Graphics 6200. If I'm not wrong about, you don't have installed latest graphics driver. 

1. yes it does not solve my problem

2. what updates should i install?

https://downloadcenter.intel.com/product/89174/Intel-Iris-Pro-Graphics-6200

Do you make use of additional anti-virus software (Avast, Bitdefender, Avira...)?

no i don't use any additional anti-virus software. i stick by windows defender

ok so i tried to install them but it turns out i already installed the latest graphics driver

Another idea: Give admin rights to "Steam.exe" and to "Endless Space 2.exe" files (right mouse click on each file, choose properties -> compatibility -> allow admin rights).

..where would i do that

Check box: "Run this program as an administrator" ?

doing that didnt do anything, it still doesn't show the menu :<

Does pressing Shift + F10 do anything?

no

update: i wish i could ask for a refund for this piece of literal trash of a game. this is a waste of my fucking money

Be patient. Someone with more ability than I will be able to help you in the future.

5Echo2 wrote:

update: i wish i could ask for a refund for this piece of literal trash of a game. this is a waste of my fucking money

Yeah it is super frustrating when a game won't even launch on pretty common hardware. Reading through your output log file, it appears ES2 can't find the Mono application files (Mono is an app that ES2 needs to work, steam is supposed to install it when it installes the game)

Can you check to see if these files from your log are actually missing?

Fallback handler could not load library 
C:/Program Files (x86)/Steam/steamapps/common/Endless Space 2/EndlessSpace2_Data/Mono/libc
C:/Program Files (x86)/Steam/steamapps/common/Endless Space 2/EndlessSpace2_Data/Mono/.\libc 
C:/Program Files (x86)/Steam/steamapps/common/Endless Space 2/EndlessSpace2_Data/Mono/libc 
Windows mono path not found: C:\Program Files (x86)\Steam\steamapps\mono\mono\mini\mono.exe

apparently the mono file doesnt even exist on my computer. it's not even there

https://steamcommunity.com/app/289130/discussions/0/617321352067840940/?ctp=2  try this

sorry but. should i install the latest version or specifically 4.5.1? i feel weird about downloading 4.5.1 since the post is from 2014 and i am not sure if it will work if i dont use 4.5.1

Latest

This error has come up in other threads.

If the game freezes when making a new game, try changing the galaxy density.

Updating to the latest version of Windows 10 has fixed it.

You can also try set "-force-opengl" in the Steam launch options. To do so, right click the game in Steam, go to properies, then click on "Set Launch Options...". That has fixed it.

If you are missing Mono you can also try installing it then copying the Mono folder to steamapps. You can find the installer for Mono here. I haven't actually seen this fix or the ones below work. The real problem is not that you are missing Mono, it looks for something in Microsoft .NET and when it can't find that it resorts to looking for Mono.

This could be caused by not having Microsoft .NET Framework 4.5.2. You can download it here.

You can try installing C++ Redistributables (vcredist). It can be found here: x86 (32 bit OS) x64 (64 bit OS)

You can also try going to the "C:/Program Files (x86)/Steam/steamapps/common/Endless Space 2/EndlessSpace2_Data/" Folder and deleting the mono folder then verify the games files with steam. It should redownload the folder correctly.

The devs have commented there is a known issue with Unity and non-English characters, they said: Some people using non-english OS and international characters in their steam path could not launch the game. Such characters are badly handled by the low level layer of Unity, Mono. We have performed a workaround in the code, (better than having to reinstall Steam to a path without accents)  waiting for a cleaner solution from Unity.

I have seen others propose a fix to this that involves deleting fonts which are corrupted. Are you using a non-English computer?