Cant play

Can you post your error log if you have one? It would be in your game install folder in a folder with a date for a name. You game is usually installed for Windows to:

C:/Program Files (x86)/Steam/steamapps/common/Endless Legend/

And for Mac:

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

Ok here I leave you the files

crash.dmpoutput_log.txt error.log

The error in the log is:

System.TypeInitializationException: An exception was thrown by the type initializer for Mono.CSharp.CSharpCodeCompiler ---> System.IO.FileNotFoundException: Windows mono path not found: D:\Steam\steamapps\mono\mono\mini\mono.exe  at Mono.CSharp.CSharpCodeCompiler..cctor () [0x00000] in <filename unknown>:0 

This comes up a lot these days. It pretty much means Unity is unhappy, but that could be for a lot of reasons.

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.

You've also got some more errors in there I haven't seen before. Such as:

Mismatched serialization in the builtin class 'GameObject'. (Read 15 bytes but expected 95 bytes)
and

The referenced script on this Behaviour is missing!

The data in the archives doesn't match the description in the game engine. You might have a corrupted installation.

Try verifying the integrity of your game on Steam. To do so right click the game in your library and select properties. Then to go the 'Local Files' tab and press the button 'Verify Integrity of Game Files..."