Frankly, you should almost never do this. The work required to create and maintain a unique landing page for every single influencer is a classic case of diminishing returns. It's an idea that sounds great on a whiteboard but quickly becomes a resource-draining nightmare. For 99% of your Creator Partnerships, the influencer's endorsement and the coupon code you give them are doing all the heavy lifting. The specific page they land on is far less important than the trust equity the creator has built with their audience. Your energy is much better spent optimizing your core product pages or collections for all traffic, rather than building dozens of bespoke pages that are difficult to track and maintain.
The exception to the rule is for your A-list, top-tier partners or for very specific, large-scale campaigns. As the Pilothouse crew often point out on the DTC Podcast, custom landing pages are a powerful tool when used surgically. If an influencer collaboration is the centerpiece of a major promotion, then building a dedicated page makes sense to maintain message congruency from their content all the way to checkout. Nik Sharma also drove this point home on Limited Supply, discussing how creator content should fit into a larger strategic plan. Think of it this way: a custom page isn't for an influencer, it's for a campaign that an influencer happens to be a part of. For everyone else, a unique coupon code sent to a standard product or collection page is more than enough for effective influencer marketing and tracking.