The colour itself is good, but if I had to say whether it would sell or not, I would say it wouldn't.
この場合、次のような言い方ができますよ。
ーThe colour itself is good, but if I had to say whether it would sell or not, I would say it wouldn't.
「色自体は綺麗だけど、売れるか売れないかと言えば、売れないだろう」
the colour itself「色自体」
if I had to say whether it would sell or not, ... で「売れるか売れないかと言えば・売れるか売れないかと言うと」
ご参考まで！
The color itself is beautiful but I don't think a lot of people would want to buy the product.
ご質問ありがとうございます。
・「The color itself is beautiful but I don't think a lot of people would want to buy the product.」
（意味)色[自体](https://eikaiwa.dmm.com/uknow/questions/71235/)はとても綺麗なんだけどあまりこの商品を買おうと思う人はいないと思う。
<例文>The color itself is beautiful but I don't think a lot of people would want to buy the product just because it's not a popular color.
<訳> 色自体はとても綺麗なんだけどあまりこの商品を買おうと思う人はいないと思う。その理由は色があまり人気の色じゃないから。
参考になれば幸いです。
カナダ 
アメリカ合衆国 
