Although it is possible that one of them could leave, the situation is now becoming increasingly unlikely, as the summer transfer window is about to close, making it more likely that they will remain at United, even if their role is limited to being substitutes and part of the rotation. However, they could still get some opportunities, though this also depends on their performance.
Currently, Hojlund and Zirkzee have failed at Manchester United, as their progress at Manchester United and their previous clubs shows a significant difference.
Loaning them out could be an option, but if Amorim wants to keep them for at least one more season, it is still very much possible.
I think the right decision would be letting Rasmus Hojlund go and meet his master at Bayern Leverkusen since ETH is also considering coming for him, Napoli is also interested. Zirkzee can remain in the bench and substitute for sesco. Manchester United has been unlucky lately with signing players. All their supposed world class players signed under ETH all flopped at Manchester United. Antony has rejuvenated at Real Betis but not back to the starting lineup. Hojlund has been very bad and cannot bench second in anyway. Instead of leaving all these players, why not sell them and get more money to strengthen the back? Martinez is injury prone, Leny Yoro is getting over laboured. I think the team really need to offload players and Hojlund is the best option to go.
Since the beginning, ETH has recruited players solely based on belief and according to his own preferences, without considering whether they fit the club's system and philosophy. As a result, many players ended up being disappointing despite their high prices, as some of them simply weren't suited to playing for Manchester United.
Now, if they eventually decide to release some of their attacking players, such as Hojlund, they must do so quickly, as there is only one week left before the summer transfer window closes.
Their schedule isn't too busy now, as last season didn't go well, especially since their only chance to be in the Champions League failed when they lost in the final. So, releasing at least one player wouldn't be a problem, but there might be other considerations that Amorim could take into account later, as he seems quite passive about releasing players at the moment.