If it is important to add all wikis from the list, it's not possible to add them on a personal level because of the 10 website limitation imposed by lenses. By using redirects, it is theoretically possible to address the issue, but it is not convenient due to the large number of wikis. However, this approach only creates redirects and does not solve the problem of searchability. Indie wikis are not identical to Fandom wikis.
On the problem of Fandom, you can read, for example, in this Reddit thread.
My suggestion here will be to add these wikis to the small web index or create a separate index. I believe many of these indie wikis are not commercial or, at least, not-for-profit (although they may contain ads). Also, they contain valuable user-generated and curated content which will definitely improve search quality. The problem is that they are potentially ranked worse than heavily SEO-optimized for-profit fandom wikis.
