Switching n/nn:
The existance of n/nn switches such as Ana/Anna, Anus'ia/Annusia, Anitsa/Annitsa (s.n. Anna).


Switching g/h:
There is no "h" in Russian. "H" is the Ukrainian version of the Russian "g" hence the "Russian" header spelling. See the numerous names starting with "h" in Wickenden listed as variants of "g" names.
eg. Gema Krasil'nikova