Verse:Lõis/Indo-Iranian languages
TODO: a weird reconstruction of Mitanni instead of Sanskrit?
Avestan
Middle Persian
One Middle Persian dialect in Lõis has a retroflex glissando liquid /ɭ͢d̪/ from PIIr *rd, instead of /l/ as in other dialects: guḷd-i-ḷdāḷd "red rose". Naušahri descends from this dialect, and as in Northern Sanskrit, ḷd reflexes as /ð/: guđ đođ /guð ðoð/.
Late Middle Persian in Lõis has the phonological innovations associated with Modern Persian in our timeline, like some words have w -> b. (read: it's basically Modern Persian minus the Arabic vocab, and with conservative vowels/contrastive vowel length)
Persian dialects
Naušahri
The most commonly spoken descendant of Middle Persian in Lõis, Naušahri (from Naušahr meaning Newton), is part of the Levantine sprachbund. It's most commonly written in the Latin, Avestan and Hebrew alphabets.
Phonology: a ā i ī u ū ai au -> a o e i u ø əi əu
Plurals usually are formed with the ending -o (from Middle Persian -ān, from Old Persian -ānām), but loanwords as in our timeline can be pluralized as in the source languages. Archaic dialects use -on instead. The most common source of loanwords is Bactrian, followed by Avestan, Greek, Togarmite and English.
The verbal system of Naušahri is similar to our timeline's Tajik. It uses the auxiliary stodan (to stand) for the present progressive, unlike other Levantine sprachbund languages.
Naušahri is strictly SVO, unlike our timeline's Persian (but it may be OSV for emphasis), and got rid of grammatical case; the accusative case ending -ro shifted to a topicalization suffix.
The particle e is used with noun-noun compounds but not with adjectives modifying nouns: šahr buzurg (big city) but gurbe-ye dust-e man (my friend's cat).
Greco-Persian
Another commonly spoken Middle Persian descendant in Lõis is basically "Iranian Persian but with Greek instead of Arabic".