MELIODAS MOVESET (This is my first moveset ever, so apologies of this is low-quality or if I got anything wrong.)
Side Special - Hellblaze
Dark, purple flames would generate from Meliodas's right hand. Then, he would release it, which travels forward depending on how much he charges it. The max size is the size of a max sized beam from Samus's neutral special, but it has the attributes of Hero's frizz/frizzle.
Neutral Special - Full Counter
(I think I should clarify this now, but Meliodas would use his signature sword, Lostvayne, not the first season sword shown it the gif)
This would be a counter move. Meliodas would take out Lostvayne and swing it directly in front of him. Once the counter hits, it returns the attack (projectile or physical attack) at twice more power. However, this is a predictable move with massive start lag, so cancelling your attack is a good idea when you notice Meliodas performing this move.
Up Special: Assault Mode
Although it isn't shown here, Meliodas gains bat-like wings when flying in Assault Mode. Meliodas would go to Assault Mode for this attack and sprout wings, causing him to fly up. Pretty much Pit/Dark Pit's up special.
Down Special: Meliodas Clone
Meliodas would create a clone to the right of him, who chuckles and then disappears. Then, next time Meliodas performs a special, the Meliodas clone would spawn again and perform the same special, though at half damage (Mostly helpful for side special). It would disappear completely after that, though.
Final Smash: Nemesis (I couldn't find a good image)
Meliodas would dash forward and transporting all hit opponents to a cutscence, where all the Deadly Sins release a combined a attack and then Meliodas full counters it, which hits the caught opponents. Then, the cinematic ends, dealing a ton of damage.