Henriquez's loan move from Manchester United was confirmed this morning, while Espinoza has already joined fellow Honduras Olympic star Maynor Figueroa at the Latics.
And manager Roberto Martinez has also confirmed Miyaichi, who has endured a difficult time since arriving on loan from Arsenal in the summer, could make his long-awaited comeback from an ankle injury against the League One outfit.
"Ryo has a chance for the FA Cup game," said Martinez.
"He is 80 per cent of his full fitness and is joining the main group this week.
"We hope he is going to be back very soon."
The 20-year-old has made just six appearances, and only one start, since his arrival from the Gunners.
He has been limited to just 20 minutes as a substitute since the Premier League defeat to Sunderland on September 29.