However, according to research, most of Li Bai's poems were written in the same language at that time, not in his dialect, which has little to do with where he came from. To say the least, if he wrote it in a dialect, it would be impossible to verify how a dialect was pronounced in those days.
What the academic circles can do now is to construct the homonyms of the Middle Ages and the Tang Dynasty. This homonym is constructed according to the system of rhyming. In any case, reading Tang poetry with the constructed medieval sounds can already have strict rhyme and balance.
If you want to know more about the Middle Ages, you can go to the Oriental Linguistics Network: http://www.eastling.org/, and click on the Middle Ages to make a query.