I asked someone who actually knows Church Slavonic and he confirmed my translation.
Also he said that the nominative would be "чeÑÂ" with no "ø" at the end.
I hope this helped out....at all...haha.

Actually it's wrong, as far as I know at least - I'm a student of linguistics and I also studied Old Church Slavonic

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It should be 'çõхъ' (singular). The third palatalisation didn't occur before ÑŠ, and occured only after ø, ÑŒ, ѧ => no transition Ñ…>Ñ here.
In the nominative plural you'll have 'çõÑÂø'.
In the locative (òъçõÑÂѣхъ) you also have 'ÑÂ' because, simply speaking, ú, ó, Ñ… changed to ц, ÷, Ñ before vowels of diphthongical origin.
Besides, your friend knows Church Slavonic, but this is *Old* Church Slavonic and these are two different animals

. But it should be like this in CS too.
About the pronounciation: in the 'modernized' reading, one should pronounce 'vchesyah' (because ѣ in the south was pronunced like a 'ya' but moved forward a bit - that's why the letter's name is YAt by the way

), 'cheh', 'chesi' - not 'v'chesyah' because v is hard here. But actually in that period (X century) the letters ê and ì were pronounced as vowels, approximately like very short o/u (not labialized) and i. So 'authentically' you should read [vÃ…ÂÄÂ'es'äxÃ…Â], [ÄÂexÃ…Â]. Though I don't believe you actually need all this info

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