Is it more positive scripting to say "You may hear a moment of silence as I work with your account" instead of "I will put you on hold as I work with your account" on phone conversations.
I don’t think so Weng. It’s plainer and more understandable to refer to “putting you on hold”. I don’t think changing the terminology to less common usage makes it more positive. The different, less plain-speaking, terminology might even be construed as very slightly evasive and thus slightly less positive and less respectful. There is a difference between being “on hold” (the sound is electronically disconnected) and simple silence (a person is present on the line but not speaking) - which is it?
Notice too that there is an error in, “you may hear a moment of silence”. Because you don’t really “hear” silence it is more idiomatic English to say something like, “there may be silence for a moment”, or “you may not hear anything for a moment”.
While "You may hear a moment of silence as I work with your account" may sound a lot more formal and fancy, "I'll put you on hold" is far more common.
"To hear silence" isn't exactly super common, in my opinion. I usually don't talk on the phone much but I am very familiar with "to put someone on hold". It's a conventional and slightly technical-sounding phrase. Most people will understand it right away.
I think it's better if you just stick with "put on hold".