I think the answer is four for Disgaea, and twice for Warcraft 3. What is it about remakes that make us buy things we already have over and over and over again. Same with Ports I've bought FFVII twice. Once for the Play Station and once for the Vitual Console on my PS3. For FFVII it was mostly because I didn't want to dig out my PS1, but in the case of the original Digaea each version offered something just a little different and I jumped on each one. Warcraft III is getting an overhaul and yeah I pre-purchased it even though I still have it on my computer.
I have Skyrim on PS4 and Switch. I also have LoZ:ALttP on SNES, GBA, 3DS, and SNES Classic (although that one was a gift). I bought Skyrim again so I could play it on the go. The first copy of ALttP I had was for GBA. I bought the SNES version because it was the original and I got it on 3DS so I could have it on the go but also on a better screen than the GBA SP. That was cheap but Skyrim was full price on Switch. Also, I bought the 3D remake of Ocarina of Time because the N64 version is clunky as hell. What can I say? I'm a sucker for perks.