Russian flag patterns changed several times during the reign of Peter the Great; from the Streltsy period, to pre-1712, and post 1712 pattern. There are two major wars fought against the Ottomans, 1686–1700 and 1710–11 during Peter’s reign and it is the latter which I have the most interest in and the flags will therefore be of the middle period.
Flag information is rather sketchy, in general infantry regiments carried a colonel’s colour (double-headed eagle) and each company a colour. Usually depicting palm leaves framing a gold chain and various devices such as a cross, eagle or crown in centre the ground colour could vary but red, yellow, blue, and green were most common. Eagles were either brown or black.
Following the victory at Poltava, Peter followed Charles XII southward. This campaign brought Peter an alliance with Moldavia and the Ukraine Cossacks under Ivan Skoropadsky. What is also known as the Pruth River Campaign, the Russians found themselves confronting a coalition of Ottomans, Crimean Tartars, Wallachians, remnant Swedes and Zaporishian Cossacks.
The combination of varied troop types in diverse costume will make for some interesting battles.
From Wiki: Pruth River Campaign
The Battle of Pruth River 1711 (Glasgow and District Wargaming Society)