in our language (tagalog [philippines]):
Nicholas = Nikolas
nickname = Nick, Kulas
Alexandra = Alexandra, Alessandra
nickname = Lex, Sandra
Olga = Olga (not common)
Tatiana = Tatiana (not common)
Maria = Maria, Marya
nickname = Marie, Mara, Ria, Rea
Anastasia = Anastasya
nickname = Tasya
Alexis = Alexis
nickname = Alex
more:
Alexander = Alexander
nickname = Alex, Liklik, Xander
Xenia = Zenia
nickname = Zeny
Elisaveta = Elizabeth
nickname = Beth, Bethy, Elisa, Lisa