How does the Battle Master maneuver Sweeping Attack work with extra damage, both rolled and static?

Sweeping Attack
When you hit a creature with a melee weapon attack, you can expend one superiority die to attempt to damage another creature with the same attack. Choose another creature within 5 feet of the original target and within your reach. If the original attack roll would hit the second creature, it takes damage equal to the number you roll on your superiority die. The damage is of the same type dealt by the original attack.

The description is very specific with the damage the 2nd target receives, in particular it leaves out any additional bonus damage from your ability scores. That leads me to think all other bonuses are also ignored, but I just want to confirm.

Specifically looking at whether Great Weapon Master feat bonus damage applies.

Great Weapon Master
Before you make a melee attack with a heavy weapon that you are proficient with, you can choose to take a -5 penalty to the attack roll. If the attack hits, you add +10 to the attack’s damage.

I've looked at some other questions regarding sweeping attack and it seems like the 2nd hit is not necessarily an attack, so if that's the case then the wording in the feat "if the attack hits" could make it so it does not apply to the 2nd target.

But what about enchanted weapons? Would a simple +1 weapon apply the +1 damage to the 2nd target? Or more complicated, something like the Flame Tongue?

Flame Tongue
While the sword is ablaze, it deals an extra 2d6 fire damage to any target it hits.

Does the verbiage "any target it hits" imply or require an attack, or does that bypass the attack rule?

How does the Battle Master fighter's Sweeping Attack maneuver work with extra damage, both rolled and static?

The description of the Battle Master fighter's Sweeping Attack maneuver states (PHB, p. 74; emphasis mine):

Sweeping Attack. When you hit a creature with a melee weapon attack, you can expend one superiority die to attempt to damage another creature with the same attack. Choose another creature within 5 feet of the original target and within your reach. If the original attack roll would hit the second creature, it takes damage equal to the number you roll on your superiority die. The damage is of the same type dealt by the original attack.

The description is very specific with the damage the 2nd target receives; in particular, it leaves out any bonus to your damage from your ability modifier. That leads me to think all other bonuses are also ignored, but I just want to confirm.

Specifically, I'm wondering whether the Great Weapon Master feat's bonus damage applies. The second benefit of the Great Weapon Master feat says (PHB, p. 167):

• Before you make a melee attack with a heavy weapon that you are proficient with, you can choose to take a -5 penalty to the attack roll. If the attack hits, you add +10 to the attack’s damage.

I've looked at some other questions regarding Sweeping Attack. It seems like the 2nd hit is not necessarily an attack, so if that's the case, then the wording in the feat "if the attack hits" could make it so the additional damage from Great Weapon Master does not apply to the 2nd target.

But what about enchanted weapons? Would a simple +1 weapon apply the +1 damage bonus to the 2nd target? How about something more complicated, such as the flame tongue?

The description of the flame tongue reads, in part (emphasis mine):

While the sword is ablaze, it deals an extra 2d6 fire damage to any target it hits.

Does the verbiage "any target it hits" imply or require an attack? Or does that bypass the attack rule?