\version "2.22"

slClef = {
  \override Clef.stencil =
      #(lambda (grob)
         (let* ((glyph (ly:grob-property grob 'glyph-name)))
               (cond
                ((equal? glyph "clefs.G")
                 (ly:stencil-translate (ly:stencil-rotate (ly:clef::print grob) -1.5 0 -2) '(-0.06 . 0)))
                ((equal? glyph "clefs.G_change")
                 (ly:stencil-rotate (ly:clef::print grob) -2 0 0))
                (else (ly:clef::print grob)))))
}

slClefII = {
  \override Clef.stencil =
      #(lambda (grob)
         (let* ((glyph (ly:grob-property grob 'glyph-name)))
               (cond
                ((equal? glyph "clefs.G")
                 (ly:stencil-translate (ly:stencil-rotate (ly:clef::print grob) -2.5 0 -1.5) '(-0.06 . 0)))
                ((equal? glyph "clefs.G_change")
                 (ly:stencil-rotate (ly:clef::print grob) -2.8 0 0))
                (else (ly:clef::print grob)))))
}


mI = <<
  \new Staff { \key c\major \grace {\once\hideNotes c64} c''2 e''4 g'' }
  \new Staff {\clef bass \key c\major \grace {\once\hideNotes c64} \once\override Staff.Clef.X-extent = #'(1.5 . 2) \clef "treble" c'8 g' e' g' c' g' e' g' }
>>

<<
  \new PianoStaff \mI
  \new PianoStaff \with {\slClef } \mI
  \new PianoStaff \with {\slClefII } \mI
>>

<<
  \new PianoStaff \transpose c cis \mI
  \new PianoStaff \with {\slClef } \transpose c cis  \mI
  \new PianoStaff \with {\slClefII } \transpose c cis  \mI
>>