I write a ridiculous amount on my phone, mostly using Evernote. It's a great app for syncing between my phone and my laptop, but the formatting comes through rather wonky when I paste into Word. This two step workaround has saved me a ton of time and frustration.
Step 1: AutoFormat
After pasting & selecting all the text, select AutoFormat... from the Format dropdown menu.
The defaults should be "AutoFormat now" and document type "General document"
This will change everything to your "normal" template
Step 2: Apply Style
I created a "novel" style template with all of my spacing, font, etc preferences
Select your style and it should all be correctly formatted and ready to go