What would SEO look like for a fashion brand that sells corsets and reworked jeans? What are the must keywords to be included, in your opinion? Also, are blog posts a must?
No, blog posts are not a must. They are for conveying information to your customers. If you have nothing to say, then you have nothing to post. You don’t need to post for the sake of it, but it can be a good strategy for targeting who/what/when/how/why queries about the products you sell.
Here’s a beginners guide for ecommerce keyword research that may help you: https://www.shopify.com/blog/14207073-the-beginners-guide-to-keyword-research-for-ecommerce