Is it a good idea to work with a remote business partner in the e-commerce space?

It really depends on your relationship with this person, which I didn't think you mention. Do you know him and trust him?

If you trust him that's fine. The only issue I see is the time zone difference, you'll just have to work it out between the two of you.

You could ask yourself this question: Do I really need a partner? Partner relations as it is are difficult to manage for most startups but having one on a remote basis will make it even tougher.
I personally think that avoiding partnerships unless they are absolutely critical is a good idea.
You could hire someone as an employee or you could hire someone with an understanding that he gets some equity but is not a part of the decision making process.

Feel free to try a 15 minute call to discuss more:

https://clarity.fm/asifosman/freecallAsif

"Mutual benefit" is the main idea, must be in the mind for every step of the designing of the partnership.

There is no certainty of viability, need many factors for consideration

~ Is it really viable?
Distributed teams are very common. If you are startup is not having to deal with shipping/receiving or if onsite events are not critical; then there are plenty of proven examples where a remote team is viable.
~ Will it be harder to bounce ideas and be innovative?
As long as all stakeholders communicate regularly and a system like Slack or Discord is adopted, it shouldn't be.
~ Will this kill momentum?
Only time this might is around an actual product launch where timing is critical for success. Otherwise it shouldn't impact anything.
~ What are your immediate concerns?
My only concern would be that adoption is key. If you both are unfamiliar with or haven't adopted agile methods for remote work, I think there will be some growing pains. But if you both commit fully to the process and the project, being remote shouldn't slow you down.

Nothing, not even video conferencing will replace face to face exchanges. Make sure you connect regularly face to face to keep the relationship tight and to make sure you are in control or at least aware of what is really happening when you are not present.