Is there any way to make double ended notes like this in Dorico?
Are you referring to the Bb and B-nat in the bass clef? If so, probably easiest to make two notes with shared noteheads, and make sure their column index is set to zero so they’re superimposed.
No, the double ended beamed notes - see last three pairs. Lining up I do all the time no problem.
No, Dorico doesn’t currently have the capability to show a single stem at the same rhythmic position on both sides of a centred beam.
Feature request please.
Actually not uncommon notation, although more modernist than anything else.
Have a look at this thread from August 2021, in which I devised a workaround which is relevant to your request. It is rather fiddly and it might not work for every case, but the attached picture shows what I managed to achieve for that particular example.
Not just modernist. Referring to post by @StevenJones01 , this is from the first edition of Brahms Vier Klavierstucke Op. 119.
Yet another good argument for supporting this. Not just for we cranky modernists.
[And what a nice job @StevenJones01 has done of setting it. But proper support would be far preferable.]