>>330988050 SpA Mew Psychic vs. 252 HP / 252+ SpD Regice: 24-28 (12.8 - 14.9%) -- possible 7HKO
0 SpA Mew Psychic vs. 252 HP / 252+ SpD Eviolite Chansey: 25-30 (7 - 8.4%) -- possibly the worst move ever
0 SpA Mew Psychic vs. 252 HP / 252+ SpD Blissey: 31-37 (8.5 - 10.2%) -- possibly the worst move ever
No.
If you're wanting to use other stats it might be situationally more efficient though, since its defence and special attack are much higher too.