A:Nafl Salaah is not allowed after Asr. So the only Salaah that a person can be making at that time will be Qadhaa because it is allowed. It will be obvious to those in the Masjid that you are performing Qadhaa. Thus this is not advisable because you are revealing your weakness to others without necessity. This Qadhaa of Asr must be made in the privacy of your home if it is being done after Asr of the day. This applies to Fajr too.
The other Salaahs have Sunnah Salaah after Fardh, so at the time of those Salaahs it will be okay to make the Qadhaa in the Masjid.
If no one can see you there, you may pray the Qadha of Asr and Fajr in the Musjid.
Moulana Yusuf Laher