I am aware that there is a book called Takreej Al-Mishkaat by Al-Albani, but did Hafiz Ibn Hajar ever do work on the Mishkaat? Is it titled Hidaayat Ar-Ruwaat?

All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad is His slave and Messenger.

Hafiz Ibn Hajar has a book entitled Hidaayat Ar-Ruwaat ila Takhreej Al-Masaabeeh wa Al-Mishkaat, and it is one of his works which many scholars mentioned when they wrote a biography about him, such as As-Suyooti in his book Nathm Al-'Iqyaan fee A'yaan Al-A'yaan.

Allah knows best.