Metric modulation 5/8 to 2/4. Quarter + Sixteenth note

Hello! I need to make a metric modulation from 5/8 to 2/4.
Its very simple: for a while my bassist divides the 5/8 bar exactly in half (two quarter notes tied to a sixteenth) for a while until that’s the new perception of the beat.
Now I would like to make the equivalence (quarter+sixteenth)=(quarter).
(Or is it perhaps quarter = quarter+sixteenth? will find out eventually)
Then I can just continue writing in 2/4.

The question is, I don’t know how to ask dórico to make the equation with a combined value. I obviously can’t manage that with a dotted note.
Any idea how I can do that?
All the best

For such a conversion you will probably have to calculate the change in tempo for a hidden tempo mark and then add the metric equation as text in a font like MusGlyphs.

thanks a lot!