You are in the 'chicken-and-the-egg' phase, you need to get past that. One option would be to simply pay someone for this role for a while to make it easier to achieve the success required to get someone on board who will do it for an equity stake.
Way too many people are looking for people to join their ventures that have effectively already failed. If you manage to distinguish yourself from the 40,000 vibe coded apps that were launched in the last 30 days that nobody will use then you've won half the battle.