Software Developer

Software Engineer

Is there a difference or its just cosmetics?

An engineer could be a developer but would probably be involved in some way in more aspects (architecture, usability, testing, security, etc). Anyway, in some ads maybe they use them as synonyms, but in a job offer they'll probably describe the position.

Also, if you're a developer in a small company maybe you end up doing more than development (UI design, for example) even if the hire as a developer, but in a big company you'll probably only code since they'll have more people for the different charges.

Software Developer

Software Engineer

Is there a difference

May be no difference. If one company has people who hold both titles, then someone at that company might be able to tell what the difference is. Could be one person would have title A at one company and title B at a different company. Don't worry about it.

Isn't an software engineer someone who has a degree/mastery/certain amount of study?

And a software developer is... anyone who develop a software? (including an engineer?)

So, an software engineer is a software developer but a software developer is not always an engineer... I guess?

an software engineer is a software developer but a software developer is not always an engineer... I guess?

In the game industry, "developer" is sometimes used to mean "programmer" but sometimes used as an all-inclusive term as you say.

A game programmer is a game developer, but a game developer is not always a game programmer.

The software industry could be very different. Games are both software and entertainment (closer to entertainment than software).