I have a csv file which contains EarningsperShare data for every quarter in this format:

Symbol, Date of release, EPS

How do I get these values in a DataSeries?

Only by creating a full-fledged fundamental data provider.

P.S. It's a bit surprising that there wasn't demand for it before but perhaps it's uncommon to get fundamentals in CSV files. And if some vendor like YCharts or Quandl provides them we rather build a standalone fundamental data provider which is way more convenient to use. Creating a "CSV fundamental provider" as something more universal than a single-user solution might not be very intuitive from a design standpoint. In other words much bang for little buck.

An easy alternative is FillSeriesFromFile from Community Components library yet this will not let you create a fundamental DataSeries as per the topic title. Just a regular DataSeries.

A regular DataSeries is all I need indeed. But if I understand it correct I have to create a new file out of the original file, that it would fit with the format needs of FillSeriesFromFile. Is there a way to create a DataSeries by code out of the original file?

Your understanding is correct. FillSeriesFromFile follows an established template to which your data does not align well. Creating a new file seems like the most straightforward option. You need to delete the first column and the header (if present).

Depending on your preference, deleting a column from CSV file can be accomplished with a variety of tools: scripts (batch files, Powershell, AutoIT), text editors (think macros), or even with a few lines of WealthScript. For example, here's how to remove the first column and delete the header (if req'd) in Notepad++.

EDIT

In WealthScript it could be as simple as...

CODE:
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