mariusz1984_katowice,
Tominškova is not via ferrata route. It is steep route with some exposed parts. Those parts are well secured. Over its entire length, only small part is exposed and therefore there is mostly no need for technical protection. Just so you will not be disappointed.
However, in winter conditions it is not recommended.
The amount of precipitation will probably be low, but Tominškova face north, so the snow might last until next season. In that case pick some other route.
I do not want to judge you or assess your capabilities, use your own judgment, but in winter conditions, ascent from Krma is nothing special. It is quite popular, you certainly won't be alone. If you get lucky, you might even make it to the top.
I would recommend you to postpone your visit, this weekend will not be best for mountaineering much over 2000m. Sunday may be OK, but as mentioned before, pick something easy, like Debela Peč from Pokljuka. It's still beautiful and just over 2000m. Take ice axe and crampons.
If you would like to visit Julian Alps, follow the forum, you might find some company for winter ascent.
Good luck,
Rok