Nikko train frequency and transfer

I'm intersted in traveling in Nikko area this autumn.

Is the train route from Tobu-Nikko station to Kinugawa-Onsen station a direct one? Or do I need to transfer to/from Shimo-imaichi first?

I also need to know the frequency of these trains in Nikko (worst case, do I need to wait more than 30 minutes to board or transfer between trains?).

Thanks!

Is the train route from Tobu-Nikko station to Kinugawa-Onsen station a direct one?

No.

Or do I need to transfer to/from Shimo-imaichi first?

Yes.

It is explained on the following page:
http://www.japan-guide.com/e/e3876.html?aFROM=3800_3875

I also need to know the frequency of these trains in Nikko (worst case, do I need to wait more than 30 minutes to board or transfer between trains?).

You can look up the timetables on the following website (enter "Tobunikko" and "Kinugawaonsen":
http://www.hyperdia.com/

There are usually connections every 15-40 minutes.