I recently started a soft-core porn account, without Adult material, just pictures and every tweet appears in Search without problem - just checked. I post a tweet, then RT from a big account and from there on, the algorithm picks it up.
What you need to make sure is that:
1) Your account is NOT flagged as containing adult material
2) Your account does not have a potentially sensitive content warning
3) In settings make sure the "Mark media you post as having material that may be sensitive" is turned OFF
4) In settings make sure the "Display media that may contain sensitive content" is turned OFF
4.1) BONUS: Its better to have Twitter Premium or Premium+
in 7 days:
Every good tweet gets thousands of Retweets, tens of thousands of likes, hundreds of thousands impressions.
When people interact with your account, even if they're just scrolling thorough your posts (watch time), they will start getting your Tweets put into their "For you" page.
In my opinion its better to focus on getting regular engagement on normal tweets rather than using the Search to drive in traffic.
If you wanna see how abusing the algorithm works, you can check this account:
https://x.com/Monika_Sharma44 - although this specific account does not have Premium sub, it still works because people 24/7 interact with their Tweets.
Hope this helps