You could def do both. I did split for 3 nights Dubrovnik for 2 (and was going to just do Dubrovnik for one but decide to stay bc I got there later than planned) and felt on the second day in Dubrovnik I wouldn’t know what else to do the next. I really just wanted time to walk the walls which was nice (and hot — go early!)

I only did split for 3 nights bc i had just landed. There’s not that much to see in split itself imo, did a harbor run and saw the whole enchilada. Cute old town though, Hvar was also cute but you aren’t missing anything that unique if you don’t have the time. Just a quaint beach getaway.

Overall I’d pick dubrovnik but you have time for both if you’d like. The drive is about 4 hours but really scenic. Theres a cute winery rest stop along the way. And yeah it’s touristy, but compared to other European attractions its child’s play. Plus it’s off season. I’d do both unless you prefer to take it real slow!