No, You cannot combine attacks with booming blade.
Both Booming Blade and Green Flame Blade say the following:
As part of the action used to cast this spell, you must make a melee attack with a weapon against one creature within the spell's range
This means that these cantrips do not require you to take the Attack action, they require you to take the Cast a Spell action.
If we look at extra attack, it is defined as:
Beginning at 5th level, you can Attack twice, instead of once, whenever you take the Attack action on Your Turn.
No Attack action is taken, so no extra attacks can be used. Additionally, two weapon fighting states:
When you take the Attack action and attack with a light melee weapon that you’re holding in one hand, you can use a bonus action to attack with a different light melee weapon that you’re holding in the other hand.
Again, no attack action is taken, so you cant use a bonus action to make an off hand attack.
In your scenario, you can cast hunter's mark or hex, and then the hit from the booming blade will trigger those effects, as well as sneak attack (if the conditions are met), but you will be unable to make more attacks after that.
Action surge gives you another whole action, which you can use to cast a spell, like Booming Blade which will give you one more attack, or if you just use a regular attack action, extra attack and two weapon fighting could apply.
One creature is affected by Thunderous Smite, both affected by Booming Blade
The wording on Thunderous Smite is pretty unambiguous:
The first time you hit with a melee weapon attack during this spell's duration, your weapon rings with thunder...
Regardless of the circumstances of Booming Blade, and it being twinned, only one of those melee strikes will be allowed to benefit from Thunderous Smite.
There's no restriction on Booming Blade being used with Thunderous Smite, though, and Booming Blade is perfectly viable to use with the Twinned Spell metamagic, because it satisfies the requirements of only affecting a single target. So this is still a very powerful combo, even if you can't apply the smite damage to both targets.
Best Answer
Yes, You Can!
Booming Blade is a cantrip with a one action casting time and Wrathful Smite is a Bonus Action Spell.
PHB, 202 States:
This fulfill that requirement - the Cantrip Action and the Bonus Action Spell slot.
Concentrate until you hit
It's also good to note that Wrathful Smite is a concentration spell and you can maintain that concentration until you actually hit the target. You can also cast the Wrathful Smite before Booming Blade so that when you hit, it's ready to go.
But should you?
This one is more up to you and the given situation, but it's something to consider. You get another d6 of damage (psychic), but the frightened condition only prevents the target from moving towards you. The booming blade doesn't trigger without movement and now the target has no reason to chase you (and in fact, can't.) There definitely are times and places, but in general divine smites are a better use of your spell slots unless you can make the frightened rider (or other spell smite rider) work for you beyond just damage.