The Microsoft Print to PDF driver works differently on Edge and IE. On Edge, it produces a PDF where each page is an image, so none of the elements on the page can be selected and keyword search isn't possible. If the document is largely text, a 'normal' PDF like the one produced on IE will often have a smaller file size.
If the size of the PDF produced by Edge is a problem, use the Save as PDF printer driver instead. This will be very like the one produced on IE. There are very few situations where using the Save as PDF driver in Edge isn't to be preferred.