prall / mordent with accidentals

[Gianmaria Lari]

What's the standard way to engrave a prall/mordent with accidentals? 

I found online these two solutions but would like to know if there is anything more "standard".

mordentsharp = \mordent _\markup { \tiny \sharp }

{a2^\mordentsharp}

mordentsharp = ^\markup \left-align \center-column { 

    \musicglyph #"scripts.mordent" \raise #1.0 \tiny\sharp 

   } 

{a2^\mordentsharp}   

P.S. The first one put the sharp above the mordent. How can we put it below the mordent?