I have been looking online to see if their are any followers of Hongs Religion/Cult in the modern day and I have not been able to find anything. Considering how many people where dedicated to his religion I would have thought there would be offshoots or remnants at least for a short while after his rebellion was crushed. What happened to believers of the supposed brother of Jesus Christ after his death, and does anybody still believe in him today?
This is something on which frustratingly little material has been consolidated, but I discuss it in this past answer. It is, to be fair, quite an old one that I may update at some point, but it is about the best summary I can provide. While there were definitely refugees from the kingdom, including Hong Xiuquan's nephew Hong Quanfu, the core infrastructure of its religion was so comprehensively crushed that its wider survival was nigh-impossible.