The head coach has already expressed his interest in making summer swoops for Matt Macey, Owen Dale & Joe Pigott, who have starred since his arrival.
Not just that but the 36-year-old also has the task of determining who he wants to keep with 10 of his permanent senior men out of contract at the end of the season.
But as Mousinho looks to build his side for the next term, what are the chances of his current loan members remaining at Fratton Park?
We’ve taken a look at the 34 men who joined the Blues on a temporary basis since the Eisner era began in 2017 to see if any judgments can be made ahead of this summer’s talks.
Forgotten any of these names?
13. Andre Green
The winger scored five goals in 12 outings for the Blues in all competitions during the 2018-19 campaign. He was recalled by Aston Villa in January 2019 and would play a key role in their promotion to the Premier League. Green now appears for Slovakian side Slovan Bratislava. Photo: Joe Pepler
14. James Vaughan
Another striker who had an unsuccessful stay at Fratton Park, making just 11 outings on loan from Wigan during the second half of the 2018-18 season. He retired in 2021, aged 32. Photo: Joe Pepler
15. Viv Solomon-Otabor
I’m sure his offside goal against Peterborough still haunts many of the Fratton faithful to this day. He joined in January 2019 and made 10 outings during his loan spell from Birmingham. The winger now plays for Ukrainian side Rukh Lviv. Photo: Joe Pepler
16. Omar Bogle
The striker arrived from Cardiff with the challenge of firing Pompey to promotion in 2019. Bogle scored five goals in 12 league outings at Fratton Park and now plays for League Two outfit Newport. Photo: Joe Pepler