comments transferred
How are comments written in cells transferred when data is moved
From one Google Sheet table to another while using a function
QUERY+IMPORTRANGE

comments transferred
How are comments written in cells transferred when data is moved
From one Google Sheet table to another while using a function
QUERY+IMPORTRANGE

At the moment it's not possible to show notes or comments by using IMPORTRANGE
You can fill out a Feature Idea to add that functionality into Google Sheets on https://www.googlecloudcommunity.com/gc/Feature-Ideas/gh-p/workspace-ideas-group
As a workaround, if you copy and paste the cells, comments and notes will be copied over, but you can do it programmatically in Google Apps Script by using copyTo
// The code below copies the first 5 columns over to the 6th column.
var sheet = SpreadsheetApp.getActiveSheet();
var rangeToCopy = sheet.getRange(1, 1, sheet.getMaxRows(), 5);
rangeToCopy.copyTo(sheet.getRange(1, 6));