Is the ruling on working in the tailoring and sewing of tight jeans for men similar to its ruling for women, or is there a difference?

The default rule regarding clothing is permissibility, except for what the Sharia has explicitly excluded, due to the generality of Allah’s Almighty sayings: (It is He who created for you all of that which is on the earth) and (Say, "Who has forbidden the adornment of Allah which He has produced for His servants and the good things of provision?").

The conditions for men's clothing are that it must cover the 'awrah (from the navel to the knee), that it not be transparent such that it reveals the color of the 'awrah, nor tight such that it defines the body parts, and that it not involve imitation of disbelievers, women, or immoral people.

If the trousers are wide and free from any of the aforementioned prohibitions, then selling them is permissible. However, if they are transparent or tight, revealing the 'awrah, or involve imitation of disbelievers or immoral people, then selling them is not permissible, as it constitutes aiding in sin and abandoning the obligatory advice, and due to Allah's Almighty saying: (And cooperate in righteousness and piety, but do not cooperate in sin and aggression).