my remaster
You can't remaster something you did not create in the first place. Or have the rights to and the source codes.
If you created a game that looks suspicously like an old game from 20 years ago and did in fact not violate any copyrights or trademarks, you might be good. There are plenty of games that are knock offs of inspired by other games. Some even better than the original.
If you repurposed the old game files, use the old title and act in a way that someone could mistake you for the original creator (by using the term remaster for example), it looks less good. Ask yourself, if you could claim copyright and more importantly trademarks for your content or not.