This one gives me Line Break *** Paragraph break, and also does it in one go for all paragraphs, whatever the length, but isn't what I need.
I need asterisks at the beginning of the next paragraph, following the paragraph break hit at the end of the previous one, like this:

"Some say he came up with the Boleyns, the queen’s family. PB

***Some say it is whole through the late Cardinal Wolsey...


In other words, the previous paragraph needs to end with a paragraph break and the next one to begin with ***. The first tweak to the script does this except for the hitch with longer paragraphs, and the second one would be perfect except for the additional paragraph break following the asterisks.

I use this autohotkey script to move to the space between paragraphs and start typing in red color:

#IfWinActive ahk_class OpusApp
^2::
Send ^{Down}
Send ^{Down}
Send ^{Left}
Send {Enter}
{ oWord := ComObjActive("Word.Application") ; MS Word object wdColorDarkRed = 128 oWord.Selection.Font.Color := wdColorDarkRed }
return


When I finish the translation I simply replace all instances of ^p*** with a space, remove all the original text which is in black color and get the translated parts glued into the originally sized paragraph.
Probably not the most elegant way of doing this but does the job for me.