U.S Customer seized shipment?

Yep, you are responsible to know what is coming into the country which you already know, and you didn;t ask a question, you made a statement.

You do have some choices, but you will have to determine which one you want to do. The smart thing is to abandon because you will have a lot of lawyer fees and court costs and you will lose the merchandise anyway

Cut your losses and try to put in a credit card dispute if paid for by credit card or PayPal, if you sent a money order, you are just out the money

Assuming this was not something illegal, like drugs, you're right that it is the seller who is in the wrong. Customs is trying to protect you from being scammed out of your money. However, there's little they can do to a seller in another country unless the police in that country cooperate. You're also not going to get very far trying to take court action against a seller in another country. What option you take will depend partly on how much money it was.

Abandon is your best option. That just means they destroy the counterfeit goods

Call your credit card company or PayPal, however you paid, and dispute the transaction

Don't take court action, it will cost more than th value of the items. And you don't want to petition, that's where you have to provide proof the item is authentic and not counterfeit. You don't have that proof. And you definitely don't want Offer in Compromise which gets the IRS involved and will drag on forever and involve audits

yes -- it's your risk when you buy products from overseas. the legit owners of that brand have asserted that they are being harmed by counterfeits and US Customs is seizing all such counterfeits they find. the US government is NOT responsible for your attempt to buy deeply discounted goods and will not get involved in your lawsuit against the seller.

basically -- you've lost your money. my guess is the amount is so small that bringing suit in a foreign country is not practical.,

I`m guessing you didnt pay by Paypal or CC as you just claim back from them and write the seller a stinker of a review

Contact your credit card company and see if you can dispute the charge.

You made a good-faith offer but the good faith was not reciprocated by the seller, so you may be able to make them eat the cost.

What I'm more concern is will I be forced to pay any penalty?