return_dict = {k: list(v) for k, v in list(d.items())}
counts = Counter([a for v in list(return_dict.values()) for a in v])
for v in list(return_dict.values()):
    for a in v:
        if counts[a] > 1:
            v.remove(a)
print(d)
print(return_dict)
Check for duplicate elements in lists in a dictionary in Python