A noun appearing as G. cwîr “cream” in the Gnomish Lexicon of the 1910s (GL/28), clearly related to ᴱQ. qirme “cream” and thus derived from the early root ᴱ√QIŘI (QL/77).
Neo-Sindarin: I would adapt this word as ᴺS. pîr “cream” for purposes of Neo-Sindarin from a Neo-Root ᴺ√KWIR “stir”, with ancient kw becoming p as was usual in Sindarin.
A noun appearing as ᴱQ. qirme “cream” in the Qenya Lexicon of the 1910s under the early root ᴱ√QIŘI [QIÐI] (QL/77).
Neo-Quenya: I would retain this word as ᴺQ. quirmë “cream” for purposes of Neo-Quenya based on a Neo-Root ᴺ√KWIR “stir”.