I like these new abilities more! I'll only list the ones I think need additional work, assuming that all the "+ chance to do X" effects only can happen on a successful hit(?):
Originally Posted by Maximuuus
3.1) LACERATE (Slashing weapons)
- use cost = action + bonus action
- effects = weapon damage + chance to inflict bleeding (-2HP / turn) AND target has -2 on Constitution ST for 1 turn
Old Version:
3.1) LACERATE (Slashing weapons)
- cooldown = once per turn
- use cost = action + bonus action
- effects = damage (weapon damage -2) + chance to inflict bleeding for 1 turn (-2HP / turn) + target has disadvantage on Constitution ST for 1 turn
Good, assuming that the enemy gets a save on each subsequent turn to remove the bleeding (or it only lasts a turn or 2).

Originally Posted by Maximuuus
3.2) CONCUSSIVE SMASH (Bludgeoning weapons)
- use cost = action + bonus action
- effects = weapon damage + chance to block the target's bonus action and reaction AND target has -2 on Wisdom ST for 1 turn
Old Version:
3.2) CONCUSSIVE SMASH (Bludgeoning weapons)
- cooldown = once per turn
- use cost = action + bonus action
- effects = damage (weapon damage -2) + chance to block the target's bonus action and reaction for 1 turn + target has disadvantage on Wisdom ST for 1 turn
There are a lot of effects here, probably making it too strong. If full weapon damage -> I'd suggest only blocking reactions.

Originally Posted by Maximuuus
4.1) CLEAVE (2H weapons)
- use cost = action + bonus action
- effects = damage (weapon damage / 2) on 3 enemies
Old Version:
4.1) CLEAVE (2H weapons)
- cooldown = once per turn
- use cost = action + bonus action
- effects = damage (weapon damage / 2) on 3 enemies
You could probably even remove the hard limit on # of enemies. If there are somehow 4 enemies within 5 feet, lucky you!

Originally Posted by Maximuuus
4.5) WEAKENING STRIKE (Club, Greatclub, Mace, Morningstar, Warhammer)
- use cost = action
- effect = weapon damage /2 + chance to inflict -2 to the target's next attack roll
Old Version:
4.5) HEARTSTOPPER / WEAKENING STRIKE (still not sure) (Club, Greatclub, Mace, Morningstar, Warhammer)
- cooldown = once per turn
- use cost = action
- effect = damage (1D4 + modifier) + chance to disarm the enemy
Possibly too weak? Compare it to Topple, Crippling Strike, and Pommel Strike: -2 on enemy's next attack roll is weaker than the other effects.
A -3 is probably better.