Triplet and straight feels on different staves?

I wonder if there is a way I can emulate this particular part of the score I am looking at?

I understand that, in Dorico, beat lengths are fixed across all staves in your project, regardless of the time signature. Thus, the barlines on a staff with 12/8 will not align in the vertical time grid with those in 4/4

Is there any way of emulating what the composer intends below, namely that each beat has a triplet feel for some instruments, and has written those parts in 12/8 and reverts to 4/4 a few bars later. However, other instruments carry on playing in 4/4 throughout.

Of course in Dorico I will probably have to stay with 4/4 throughout for all instruments and explicitly write triplets for those parts that the composer had written as 12/8 … even though I suppose he wanted to make the score a little less cluttered with triplet beams and whatnot.

What’s intended:
Triplet feel beats

Brilliant! I knew I wouldn’t have been the first to need to do this.

La cosa che mi fa arrabbiare è che con MuseScore l’operazione è semplicissima: è sufficiente tenere il tasto command premuto e trascinare dalla paletta alla misura vuota la frazione del tempo nuovo e tutto è perfetto! Io spero molto che nella prossima versione si colmino queste mancanze (e non sono poche).
Buon lavoro a tutto il team di Dorico.