If your product page URL is getting a good chunk of organic traffic, then ideally don't risk changing the URL. In saying that, if you have to change a handle, a redirect is usually fine.
However, if you are not getting any organic clicks, then doesn't matter you're worrying about something that isn't even a problem. Just change it.
If done correctly the redirect should transfer the link and topic equity over to the new page URL. As long as the on-page is mostly the same, then any organic visibility or rankings will tend to follow. Doing the odd 301 redirect in Shopify is not really a problem at all. If you are doing them so frequently that you end up with chained redirects, then that could be a problem.
Ideally (for SEO) you would take a more data based and strategic approach based on keyword research and opportunity identification. Name it good once and you should be mostly sorted. The premise being that you want to pick product titles and page content that include a head topic and sub-topics that people are (already) searching for. So call garden hose a "garden hose" somewhere in the product name and not a "watering pipe" or whatever other branded weirdness gets dreamed up.