# задаём настройки стилей для отрисовки в цикле
line_styles = {'na_players': {'color': 'red', 'width': 4},
               'eu_players': {'color': 'green', 'width': 3, 'dash': 'dash'},
               'jp_players': {'color': 'blue', 'width': 2, 'dash': 'dot'},
               'other_players': {'color': 'orange', 'width': 1, 'dash': 'dash'}}

#формируем графики для отрисовки
data_games_by_year = []
for column in line_styles.keys():
    data_games_by_year += [go.Scatter(x = games_grouped['year_of_release'],
                                      y = games_grouped[column],
                                      mode = 'lines',
                                      line = line_styles[...],
                                      name = column)]