Re: the first plague in Ex 7:18 and 21 only say that the Eygptians will not be able to drink the water. Nothing about Israel.Israel suffered the first 3 plagues along with Egypt.
Re: the second plague in Ex 8:3 and 4 specifically says that the frogs will "come upon your people" (referring to Egyptians), including the officials. Nothing about Israel.
Re: the third plague in Ex 8 there is no mention of either Egyptians or Israelites, just that gnats were everywhere in the land.
My view is that the "land of Goshen" was unfavorable to the Egyptians, who "loathed" shepherds, per Gen 46:43. The plagues specifically targeted the Egyptians.
I see no reason to assume that Israel was affected by any of the plagues. But if you find any solid evidence for that, please share.