Your now able to add some Enchantment-Effects that modify Attributes from the Player. Attributes apply depending on which slot-groups are present.

To apply a new Attribute-Enchanting Effect you can add following to the EnchantmentBuilder:

ENCHANTMENT_BUILDER.effect(new AttributeEnchantEffect(Attribute.GENERIC_MAX_HEALTH, new LevelBasedValue.Linear(1f,1f), AttributeEnchantEffect.Operation.ADD_VALUE))

The LevelBasedValue allows to modify the impact of the Enchanting-level and has some variations:
Clamped,
Fraction,
LevelsSquared,
Linear,
Lookup,
Constant