Since Russell originally is French for "Redhead" - рыжый - there is no equivalent in Russian or the other Slav languages, which have a very different tradition for personal names. Yet, it could be a surname, like Czech Červený, also common in Slovak - and from there in Hungarian: Cserveny. Ukrainians also have their Червоненко. Russian Краснов Originally in Russian красный meant pretty, not red. Hence the Red Square and прекрасный - not - G-d forbid! - прекрасивый... So keep calling them Рассель - мягкий знак and everything... After all, Russell the Brit was a fellow traveller - a friend of the Bolsheviks and an enemy of the West. And Russell Crowe does not care.
The Russian language equivalent of the name Lauren is ΠΠΎΡΠ΅Π½ (pronounced as "Loren").
The Russian language equivalent of the name Ryan is Π Π°ΠΉΠ°Π½ (pronounced 'ra-yahn').
The Russian language equivalent of the name Dmitry is Dmitriy (ΠΠΌΠΈΡΡΠΈΠΉ).
Клиффорд. Pretty much a direct translation of the name.
The Russian language equivalent of the name Mark is ΠΠ°ΡΠΊ (pronounced "mark").
Douwg
Matvey
Бріттні Brittni
Морин Morin
Juana = Ivana (Ивана)
Чарльз (Charl'ze) is how you would spell the name in Russian, if that's what you mean.
Jonny, Johnny