How? The only S.H.I.E.L.D. agent was the Steamstress, lol.
the scene where peter is introduced to Quentin beck in far from home (2024), there was fury, hill and a few other agents like Sergi (not sure if that was his name or not lol) and yes, the seamstress was part of that gang too but again the further along since AoS finished up in 2020, shield gets diminished dramatically until fury's agents are all skrulls/aliens by the time of the marvels although just thinking about fury's personal timeline makes me think there are now 2 separate groups (small group of Human Shield agents on earth) and (the skrulls/aliens running saber).
2018 - contacts shield agent before being snapped
2023 - gets blipped back, attends tony stark's funeral, tells gravik and his skrull agents to collect DNA and leaves earth, gets skrull agent to recruit Monica to saber
2024 - Fury is relaxing on saber with Skrulls and Monica, while Talos and Wife be fury and hill co-ordinating the small cell of Shield agents on earth
2025 - Fury returns to earth, re-unites with Talos and hill, hill is killed, skrulls are massacred by gravik, fury and co. stops gravik's rebellion, heads back to saber with his skrull wife, Fury and Monica, visit the khan house after power entanglement, fury takes the khans to saber which is run by Humans/Skrulls in disguise/aliens or all of the above.
so the skrulls helping to build saber in 2024, where they still on saber just disguised as humans or did they go and live in russia and then get wiped out by gravik?