Yes, buyers can reply to your thank you email and when they do you will get their email to the email address connected with your eBay account.
You can also change the email address that buyers see and reply to.
If you want to change this email address follow these steps:
1. Login to your control panel.
2. Go to your “settings” tab.
3. Go to “Contact Info & Social Accounts”.
4. Change your contact email to the email you want buyers to reply to.
5. Click on “Save” to save changes.
That's it! Now when buyers reply to your thank you email it will arrive at this email address.
Feel free to leave a comment here below if you have any other related questions.