is this possible with dorico?

Is it possible to engrave something like the attached example in Dorico (litte notes which show the 2nd trill note) - it is actually from a Pierre Boulez piece.
Bildschirmfoto 2018-08-28 um 16.23.22.png

There are workarounds
https://www.steinberg.net/forums/viewtopic.php?t=139656

Also investigate adding parentheses to noteheads in the new Engrave > Notehead Sets dialog.

Auxiliary notes for trills are not part of Dorico’s current feature set, but they are certainly planned for the future.