Hi there John
Thank you for your post as it has prompted me to explore this issue further.
I guess the issue is whether ereaders are able to render/represent the transliteration characters that you use correctly.
All of the fonts in the list render the transliteration characters according to the unicode conventions found here: https://www.brill.com/downloads/Simple_Arabic_transliteration.pdf I think that this is probably the safest way to transliterate the arabic language that will cross platforms etc.
There are quite a few older fonts that do not conform to these conventions like OI-Beyrut (https://www.samuli-schielke.de/oib.htm) etc but i think that these fall under the following description:
“over the years many academics created all kinds of fonts with special characters for their own private or shared usage. The problem with these fonts is that they are private, they do not follow any agreement with other computers on how these characters are to be displayed. On your own machine, that does not matter, you can type, edit, print with these private fonts in any program, old or new. But if you want to share your documents with others, colleagues, or in particular: with your publisher, the diacritics will disappear or get “transformed” into something else.” (taken from https://org.uib.no/smi/ksv/diacs.html – A very good online resource on transliteration of Arabic and arabic fonts worth checking out)
So i guess this is what you are trying to avoid, characters transforming into something else in the ebook. But it would seem to me though that the unicode fonts are the safest way forward. I personally believe that it is worth taking the time to do this, the Ascii method is fine, it does the job, but using the unicode characters i feel look much better.
I have a couple of books that have both arabic script and transliteration and i will be having them converted into ebooks. So i phoned the company who does that for me this morning and asked them about this issue. They hadn’t been presented with it before, so i am going to send them a couple of sample pages and they will let me know if the unicode renders properly or not. I will let you know here what their feedback is.
Thanks again
Best wishes
Andy