Clothing for Men

Q: I play badminton and to play that I need to wear nikkar which is above the knee. Because in this game rapid movements are required which is very hard wearing trouser. Is it permissible to wear this during game?

Q: I require the following clarifications regarding wearing a Topi.

1. Did Rasul Allah Sallallaahu Alaihiwa Sallam and the Sahaabah Radhi Allahu ​Anhum nurture the habit of wearing Topi during their lifetime? Sahih Bukhari 275 mentions of an occasion when Rasul Allah Sallallaahu Alaihiwa Sallam led the Jamaath having just completed his Ghusl with water dripping from his hair. Similarly other references that Rasul Allah Sallallaahu Alaihiwa Sallam did not wear Topi are mentioned in ​Nasa'i -5219, 4980,  Muslim - 4666, 4680, 4270 Bukhari - 3548, 352, 353 and Abu Dawood - 592, 3658.
2. Did not this practise actually originate in Turkey when it became the capital of the Islamic empire, whose citizens had a traditional habit of wearing the tall and round Topi?
3. Why do Muslims in many countries offer Salaah without the Topi? Are they going against the Deen? Is their Salaah not valid? 
4. Then why do not Muslims who go on Haj/Umrah not wear a Topi (covering their head) by un-stitched cloth like they wear for Ihram?
5. So, going by the above Sahih Hadith, is it still mandatory to wear the Topi ? Is it not a Bid'ah?

Q: Is it permissible to wear track pants or 3/4 shorts and a t-shirt when engaging in some sports to keep fit?

Q: When playing some sport is it fine to do so without a topi?

Q: I read the hadith "The difference between us and the pagans is that we wear the 'imama on top of the qalansuwa" (Abu Dawud). Does this mean that the mere wearing of a topi resembles the practise of the pagans and that it is better for us to wear imamas? The only problem for me wearing an imama is that it is uncommon amongst the Muslims where I live, most people including elders and teachers wear topi, and I am afraid that I give myself a higher rank than I am worth if I wear an imama. Is this a valid excuse not to wear an imama?

Q: When playing sports to keep fit e.g squash or soccer etc, is it permissible to wear 3/4 shorts and tshirt, or must one wear a short kurtha?

Q: On Bakri eid we find that many people who usually wear kurthas and sunnat libaas leave the sunnat clothing and wear 3/4 shorts and tshirt, with the excuse that we cannot make Qurbani /work with a kurtha on. Do we find this in the life of Nabi Sallallahu Alaihi Wasallam that he would wear different clothes when doing messy work etc or should one stick to wearing the kurtha when doing hard work etc?

Q: Should the thermals worn in winter under the pyjama be above the ankles or is it permissible if they are not?

Q: Is it sunnat to have one's kurtha pocket on the right hand side of the chest? And have the button flap with the right side on top of the left?

Q: We have many transgenders among us. Though they have male features, they still prefer to dress themselves as women and due to this, they are being subjected to all sorts of humiliation in our society. Does Islam classify them as males or females? Is there any Qur'anic Ayat or Sahih Hadith mentioning them?