I would recommend Google Drive, or DropBox, or Box. Until now, my favorite was Creative Cloud Drive but that is unfortunately being turned off in Feb 2024.

If File > Place, turn on Show Import Options (sometimes accomplished by holding the Shift key down as you click Place/Open) and in this second dialog box you have the ability to strip all styles out.

Also, in the realm of copy n paste, under the Edit menu, you can Paste Without Formatting.

While there is no plugin for this in InDesign, have you tried recording an Action in Photoshop?

Try Mike’s Find/ChangebyList 2017. It is a free resource:
https://trainingonsite.com/useful-resources/indesign-cc-2017-resources.html
It accomplishes 17 or so common text cleanups, and won’t harm styled paragraphs. It fixes em dashes, en dashes, quote marks, and even turns apostrophes the right way up (when used next to 2-digit year references). From my testing, it will not harm or change paragraph styles.

I have discovered that if your text has XML tags around it; the Find/Change of empty hard returns gets messed up.