I think it's a bit of a mix with some things looking better in one game, and others looking better in the other; but the thing is RF5 should be a complete upgrade from Frontier, and it isn't. The graphics of 5 definitely look higher resolution, sharper contrasts, and certain items animate (like the swaying trees). Yet, the environmental effects and animations (I'm talking things like runeys, butterflies, water and such), the detail, and the aesthetic, and even UI art and loading screens look considerably better on Frontier.
Overall, I like Frontier's look more than 5, and IMO it's one of the most underappreciated games of the franchise and the Wii/PS3/360 generation - I sank a disgusting 180 hours or more into it. it was one of my favourite 'go-to' games for two generations. I played it on and off all the way until the release of the Switch and games like Breath of the Wild & Stardew Valley. I've never been able to get into the top down Rune Factory games, even though I like the concept, they didn't grab me the same way, and Oceans had too much water (that's an IGN reference), seriously, Oceans felt like it got too far away from proper farming so I didn't really get into that one either, though it's my second most played Rune Factory game.
What is up with that ground about 2 minutes into the RF5 video? The character models look decent, and the buildings look fine. But everything in the town is sitting on top of what looks like N64 era ground, complete with angular looking hills and bumps. And those green and brown textures for the grass and trails...wow. Looks like it was spray painted on.
Frontier definitely benefits from the lower resolution. But the art direction is just so much better.
Switch Code: SW-7377-9189-3397 -- Nintendo Network ID: theRepublic -- Steam ID: theRepublic
Switch - Mario Kart 8 Deluxe (2014/2017)
Switch - Bastion (2011/2018)
Wii U - Darksiders: Warmastered Edition (2010/2017)
3DS - Pushmo (2011)
3DS - New Super Mario Bros. 2 (2012)
Mobile - The Simpson's Tapped Out and Yugioh Duel Links