Now 2021, still waiting for RTL support, We can find the below in Text Style edit
Character language
Typography script ( in this we find Arabic)
Typography language (In this we find Urdu language)
We also tried rtlfixer, but when we copy text from a website, it break text after every line and Line break sign shows on LTR style. Also it didn't support Urdu language font (see Mehr Nastaliq font, which can be download from https://en.m.fontke.com/font/19978501/download/)
I must say, it should be provided on priority basis, as there is a big market in the World, as at the moment only software, is InPage Urdu (www.inpage.com) is available for Urdu language, InDesign middle eastern version also support, but it price is very high, and like Pakistan and India, user can not afford it.
Even this editor have RTL support, so why not Affinity.
اس ایڈیٹر تک میں یہ سپورٹ موجود ہے۔
So you have to think now.
Thanks