Sweet Home on the NES; it's had an English fan translation patch forever now.

For those that might not be aware, it's frequently cited as the inspiration for Resident Evil and you can certainly see it, although it's more of an old school RPG. Don't let that dissuade you though, the RPG mechanics are light and relatively easy to manage although you'll want to look up a table for weapon values because it's super obtuse. You take control of 5 characters, each with a unique ability or item that will help you work your way through the manor. You can split them into any number of parties with a max of 3 members and move them around independently. You'll have to actively look for clues and solve a lot of item based puzzles which are pretty engaging and clever, though not difficult. Stuff like having to pick up wooden boards used to strategically bridge gaps in the rotten floor. When characters die they are permanently gone, so you'll have to find items that can be used to replace the ones they carried. While it's true that making anything 8-bit truly scary is difficult if not impossible, there's a very real tension while playing the game and the overt horror themes still set an engaging mood, even if they can't outright spook you.

I think about this game all the time, it only takes 8-10 hours on a first playthrough, probably less if you want to use a guide. Give it a try and I think you might be pleasantly surprised.

For a follow up, check out Shiryou Sensen: War of the Dead on the TurboGrafx-16 which also has a fan translation patch available. While I don't think it's ever been directly cited as an inspiration for Resident Evil 2, it's impossible not to see. Lila, a member of S-SWAT, is the spitting image of Claire Redfield ... if Claire had nuclear green colored hair. The town of Chaney Falls is being overrun by occult horrors and it seems related to the old Browning family. There's a mystery to uncover. This one is a lot rougher around the edges and gets weighed down by some tedium, definitely use a guide to help you get through this one. Still, it's worth a look. I have a fascination with these retro horror RPGs.