Thanks for your reply and thanks for checking the links I gave you. I agree this is probably because other sellers who do not understand English have used Google translate to enter the title. There are many more badly written Amazon listings for Seiwa’s products, so the best thing we can do is try to fix Seiwa's data on Amazon.
Regarding a solution, the best option will depend on Seiwa’s own goals and manpower capabilities.
「貴社が「アマゾンでの商標をSEIWAとして設定してください」というのを、単にそのまま解釈しても正しいですか。」回答は、いいえ、商標の店は、全く別の問題です(例えばここに、SamsungのAmazonでの商標の店舗があります。
https://www.amazon.com/stores/page/334EF254-D84F-4D5F-923F-736681DBA062/)
私は、アマゾンにあなたが店舗を開設するのを勧めているのではありません。私はただ、あなたがご自分の商標と製品をAmazon.comで登録するのをお勧めしています。これはシステムのバックグラウンドでの手続きであって、アマゾンにあなたがこの商標の所有者であることを証明し、あなたの製造する製品を確認するものです。これをすることで、アマゾンに商標の店舗を開設するものではありません。
Regarding your question: “Is it correct to simply interpret what you are saying, "You should establish an Amazon brand store as SEIWA"?”. No, a brand store is a completely separate topic (for example, here is Samsung’s Amazon brand store: https://www.amazon.com/stores/page/334EF254-D84F-4D5F-923F-736681DBA062/). I am not suggesting you open a storefront on Amazon, I am suggesting you simply register your brand and products with Amazon.com, which is a backend procedure and simply proves to Amazon you are the trademark holder and confirms to them what products you make. Doing this will not open a brand store on Amazon.
I think the best way forward is for Seiwa to contact Amazon Japan’s customer service, and ask how you can register your products and brand on Amazon US, we can provide you with English titles and descriptions for your products. This option I think is the best, since you have control over your brand on Amazon. But you will have to prove to Amazon you are the trademark holder, and you manufacture Seiwa products. This will require you to give Amazon written evidence, for example: Legal documents, photographs, catalogues, etc, and then enter your product data into Amazon’s system, unfortunately, this means Seiwa will have to do a lot of work.
その理由は貴方がアマゾンにおける貴方のブランド名を管理する権利があるからです。貴方は貴方が商標の保有者であり且つセイワ社の商品の製造者であることを証明しなければなりません。この方法において貴方はアマゾンへ筆致による証拠を提示しなければなりません。例示すると法的な書類、写真、カタログ等です。その後、アマゾンのシステムへ貴方の商品に関するデータを入力します。不幸なことにこの作業においてセイワ社は莫大な量の作業をしなければなりません。
Regarding your question about ".com" and "co.jp": Amazon.jp and Amazon.com are two different subsidiary companies of Amazon so they have different systems, procedures, databases, and staff. I believe Amazon.jp can give you basic information on how to deal with Amazon.com, but you will have to deal with Amazon.com directly to change your product data and register your brand for anything that appears on Amazon.com.
Regarding if we will help you register your brand on Amazon, we will help as much as we can.
Amazon.jpはAmazon.comの対処方法についての基本的な情報を提供してくれると思います。しかし、貴方は貴方の商品のデータを変更したりAmazon.comに表示される物について貴方のブランド名を登録する場合、直接Amazon.comへ連絡しなければなりません。
弊社による貴方のブランド名登録でのサポートについては、最大限に尽力します。
あなたがアマゾン上であなたの商標を登録するに当たり、お手伝いできることがありましたら、その旨ご連絡ください。
However, as you mentioned there is a shortage of personnel in Seiwa, so all of the above may require too much of your time. If that is the case, my company can try to change the names for you one-by-one from our Amazon seller account. But we will need an English catalogue published on your website, and Letter of Authorisation telling Amazon we are your authorised retailer, this is so we can prove to Amazon US that the changes we make to Amazon’s listings for Seiwa’s products are authorised by Seiwa. Both the English catalogue and letter of authorisation we can write for you. This way is much quicker and easier, but Seiwa’s brand will not be registered with Amazon.