There was a variable "fTimeScale" in TES4 etc. Who knows, is there any anologue in Creation Kit?

Type timescale in the filter textbox and hit enter. The variable will pop right up.

There is no such variable in Creation Kit. Do anybody knows, is there a way to change the scale of time (default is 1 to 30)? Or it's hardcoded now?

Click on All at the bottom of the list and you will see it.

The variable's name is (and always was in previous games) "TimeScale" - no "f"

It's a global variable, not a Gamesetting, so in the CK you change it under Miscellaneous/Global

You can also change it ingame with "Set Timescale to 10" in the console

^{Great thanks. Found it.}

As they said above, the time scale is rather simple to change, but a bit in-depth to find.

With the Skyrim.ESM loaded of course, go into the Miscellaneous section, and scroll down to the Global section, where GameDay, GameDaysPassed, GameHour, GameMonth, GameYear, PlayCredits, and finally, TimeScale is located. From there, just double click the TimeScale variable, and change it's value. I recall reading somewhere that 1 Timescale value is realtime, and the default is 30, so obviously if you're not setting it to a given setting, you can play with it less or more depending on how slow or fast time should move in your opinion.