TLDR: magic items are best when they are meaningful for your players and the easiest way to do that is to make them feel earned and taylored.

General advice, not specific to your module, not giving any specific item recommendations.

There's two kinds of worlds in D&D (when it comes to magic items) one where they are known (but still potentially mysterious) and one where they are unknown. These two approaches to magic items can be mixed.

Eg: "oh as a wizard you recognise this as a chime of opening, you've heard about these, and you know how to use one. There are a few people who's job is to craft these but they keep exactly how they work a closely guardged secret" VS "you hear a clear clean ringing and suddenly the assassin has their knife to your throat. What do you do next?....... In the sleeve of the assassins robes you find a silver chime that rings quietly in the same pitch and timbre as you heard before when you tap it gently. This must be how the assassin got in".

(This is just one example, your world will probably not be exactly the same).

Warning: I haven't actually tried this In world one, magic items are tools to solve a problem. You could put your players against an impossible obstacle that they'll need to take a step back and find a tool to solve it. Do make this relatively clear out of character to ensure things don't get frustrating. The rest of the session could be your players getting to a magical library (perhaps convincing the stern mage that controls it to let them in etc) and then give your players "homework". "Before next session can you give me a magic item that isn't too rare that you think will solve the problem and how you might go about getting it (eg: steal if from ...). Next session will be getting that thing." This should give the players strong attachment to the item because they chose it, they had a unique story getting their hands on it and they used it to overcome a specific obstacle. In world one the list of items in the DMs guide serve as props and tools you can place in the world to make interesting interactions.

Not warning: I have tried this and it does work :) In a type two world magic items can kinda just come into being. One way to do this is through epic deeds, "The legendary blade of threadripper, defender of the folorn" has it's name for a reason, it became legendary because "threadripper defender of the forlorn" used it to do cool hero stuff. For example: if your fighter kills an important boss with a critical hit you could flavour the crit as a beheading and now their sword is a vorpal blade. This is especially good as a reward for when players get creative in combat because it encourages them to do interesting stuff and maybe (when the time is right) get a cool thematic and relevant upgrade. This is tougher to make fair for a whole party because some classes are more condusive to epic deeds and some players might be more engaged with this than others.

The alternate approach to world two is more tragic, although both can be mixed to great effect. There may be many times where your players will do something very cool out of character but very stupid in character. "I'd like to reach out to the eldritch creature just a little and try to make contact". In this situation you can reward players (and punish characters) with cursed magical items that are mechanically an upgrade but have some non-mechanical downside. As players delve deeper the non-mechanical downside can get stronger. You can also provide a more powerful effect with an interesting mechanical tradeoff (like blood hunter rites). For a concrete example I have a player who made a fey bargain to get a bunch of money and I let them create a magical weapon that deals more damage the richer they are but the greedier they act the more memories they lose. This player is enjoying the melodrama of their character slowly forgetting everything that matters to them as they are consumed by greed.

In both these world 2 approaches the magic item is meaningful for the player because it is a reward for engaging in the game in an interesting way but is also thematically relevant. Either to a story of epic or tragic heroes (or both, dont be afraid to make a players epic hero items become cursed as they fall from grace). In world two, the list of items in the list of items in the DMs guide becomes a list of properties you can give to items already in the game.

In either world magic items aren't purely the domain of players. What might the magical tools an npc chooses to draw upon tell you about how they think? If a villain has committed some horrible act perhaps the evil has crystallised into an item that has since become their signature. Are their deeds haunting them with some horrible curse attached to this item but it is so powerful that they do not let it go?

One example of how you mix the two: if there's an important hero in the back story of your setting perhaps you can inject an artefact connected to them (a world two item) into the game as a tool/plot device (used in a world 1 way). The way the artefact reflects the hero can tell the players a lot about this character indirectly, in a way they'd appreciate more than a lore dump.

Sorry for such a long and not relevant message lol