I believe if Loki shape-shifted into Tony nobody would notice for a concerning amount of time. Cause both of them are such divas
Two scenarios.
One, Tony is gone on some business thing and Loki wants to have fun having control over everything.
First he avoids the avengers because he thinks they'll know.
But a few run-ins later he is getting oddly concerned as to why nobody realizes it's him. So he tries to see how far it can go
Steve: Hey Tones we need you in the hall, Clint-
Loki: No
Steve: understandable. Its his problem he can stay stuck
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Bruce: why is everything floating?
Loki: because I'm making it
Bruce: oh alright. Just glad not another one of your machines went rogue
Loki: ?????
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Thor: Thanks for the pop-tarts, Stark!
Loki: I did nothing. I hope you choke on them
Thor: oh so humble! You did buy so many that I could choke!
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Rhodey: *stares*
Loki: what
Rhodey: *squints eyes*
Loki: *confused and anxious* why are you doing that?
Rhodey: you aren't Tony *walks away*
Loki: wait HOW DID YOU KNOW?! Where are you going-
Rhodey: Tony needs a break, I'm not stopping this
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Peter: Mr. Stark! Look at this!
Loki: Don't bother me
Peter: .... Mr. Stark?
Loki: what did I say? I'm busy. Go away you pest
Peter: ....
Loki: ....
Peter: ....
Loki: *concerned at the sudden silence*
Peter: *looking absolutely terrifying and ready to fight* you're not Mr. Stark
Loki: fuck
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OR Tony and Loki learn this after an incident like above and plan to see how long it'll take for Loki to be discovered
