Answer:
Moderately could be seen as slightly more than somewhat, although the definition of somewhat includes the word moderate, so they are probably more commonly seen as synonyms. Moderately sounds more professional than saying Somewhat. "Somewhat" is defined as "to a moderate extent or by a moderate amount" while "Moderately" is "to a certain extent; quite; fairly". Under Somewhat the first similar wording is "a little bit" while under Moderately it is "somewhat and quite".