\version "2.24.3" \language "english"

% \partCombine does not handle divisi (\partCombineApart) that
%  begins inside two tied notes. Gives warning: unterminated tie
%  and does not tie the notes together.  Top part printed alone
%  does not trigger this problem (second line).
%
%  Workarounds that change the tie to a slur or omit the tie in
%  the top part but retain in the bottom part moves the divisi
%  back one note to begin on the first e natural.

FlautoTwoVI =
  \relative c'' {\clef treble \time 12/8 \key e \minor
  gs8 fs es es4 e8~
  \partCombineApart e^\markup{\small\italic "Flauto II"} d e as b cs
 }
  
ViolinoTwoVI =
  \relative c'' {\clef treble \time 12/8 \key e \minor
  gs8 fs es es4 e8~
  e_\markup{\small\italic "Violino II"} d cs as' b cs
 }
  
\score {
 \new Staff
  <<
  \set Staff.aDueText = #""
  \partCombine \FlautoTwoVI \ViolinoTwoVI
  >>
}

\score {
  \FlautoTwoVI
}