Since you want Chassidishe, here you go! (By the way, the following was quoted by the Chasam Sofer)
R’ Shimson Ostropoli asks, Where do we see that Moshe was told to warm Paroh about the Arbeh (i.e. how did he know that the 7th plague would be arbeh)?
?? ??-????: ??-??? ?????? ??-???, ???-?? ?????, ???? ??? ???? ???, ?????
There is a known rule in ????? that certain letters form groups based upon how they are said, and letter in these groups can be interchangeable. ???? form a group of guttural letters. ???? form a group of letters which are said using the lips.
So, getting back to the point, how did Moshe know to warn Paroh about Arbeh?
Hashem tells Moshe: ?? ??-???? – put the word ?? into ????.
In order ???? ??? ???? ???, ?????
???? ???- In order that I may place
???? ???, ????? these LETTERS in him. since the ? is in the same group as the ?. and the ? is in the same group as the ?. Put the letters of ?? into the word ???? replacing the letters of their group, and what are we left with (after scrambling the letters)?
????
That is how Moshe was able to tell Paroh what the 7th plague would be.