my_list_1 = [4, 5, 6, 5, 4, 7, 8, 6]
my_list_2 = [1, 7, 6, 4, 7, 9, 10, 11]

print("The first list is :")
print(my_list_1)
print("The second list is :")
print(my_list_2)

temp_set = set()
temp = []

for index, value in enumerate(my_list_1):
   if value not in temp_set:
      temp_set.add(value)
   else:
      temp.append(index)

my_result = [element for index, element in enumerate(my_list_2) if index not in temp]

print("The result is :")
print(my_result)

The first list is :
[4, 5, 6, 5, 4, 7, 8, 6]
The second list is :
[1, 7, 6, 4, 7, 9, 10, 11]
The result is :
[1, 7, 6, 9, 10]