Base Class: Rogue
Allowing for the mix of Strength with Dexterity, the Shadow Boxer is a subclass that focuses on two things. Make melee combat more viable without having to be a Monk, and allowing the player to still feel like a Rogue by going in and out of combat but allowing for multiple attacks. For people that are less interested in a magic subclass, and more interested in hitting things as much as possible in one turn, without making the class too overpowered. (Don't mind the spelling errors or how probably overpowered it is)
Light Foot, Quick Fist
Heavy Fist - when you take the attack, shove, or grapple action, you can use your bonus action to attack an additional time, also, your unarmed attack die are replaced by 1d8, reaching 2d6 at 6th level, 2d8 at 9th level and 2d10 at 14th, and 3d8 at 17th. Also, you gain proficiency with unarmed strikes. Your fists are now treated as finesse weapons. Light Foot - A number of times per short rest (equal to your dex modifier), or when you miss a melee strike against a target you can take the dodge action using a bonus action instead
Cheap Shot
At level 5, during combat, if you enter melee range, you get an opportunity melee attack. This is treated as an extra attack. At level 9 If you grapple an enemy, you can attempt to use your bonus action to deal a significant blow instead using this ability. If the hit lands deal melee damage x2. If you kill an enemy with this action while grappled, you snap the creatures neck.
Opening Strike
Opening Strike - gain advantage on any unarmed attack against an unharmed enemy. if you willing start your turn by entering the enemies melee range (and didn't start there) you also gain advantage. if you wish, you may gain an additional strike by sacrificing half move speed in your next turn. this can reduce your speed to 0.
Fists of Fury
(You will now roll 3d8 to determine melee damage) Fists of Fury. for Resistances and Immunities, your unarmed strikes are considered magical. if an enemy attack misses you, you may use your reaction to make an attack against them. If the attack is successful, the target must make a Con Save (DC = 10 + Dex + proficiency) or be stunned until the end of their next turn. if an enemy succeeds their Con save, they are immune to this effect for 24 hours (alternately, only allowed to use this a number of times = half dex modifier rounded up per short rest)