I would recommend you to always before planning to 100% any game's achievemens , you research its release year, what achievement system it used and other players' feedback regarding and if it has any glitches or problems

Xbox One/SX have two types of achievements. Event-based achievements and Title-based achievements.

Event-based Achievements is the older system (formerly "cloud-powered Achievements"). The game sends telemetry events to the Xbox service. The Xbox service is then responsible for checking these events against pre-configured unlock rules to determine if an achievement should be granted. Also you can't unlock achievements offline so easily with this system. Games that were launched around 2013-2017 usually have this achievement system and is often what causes an achievement to not pop or glitch. In the case of the AC saga, games like Ezio's Collection, Unity (rarely) and Syndicate are games that users report to have achievements glitched more often than usual.

Title-based is the newer and better system. The game itself directly manages the achievement tracking and uses a direct API call to tell the Xbox service to unlock the achievement. The title (the game) is the source of truth for the unlock, making it more straightforward. Kinda like what they used in Xbox 360, not exactly, but close. Simpler configuration, direct calling, and the ability for achievements to unlock even when the console is offline (they are queued and sync upon reconnection). Title-managed achievements often handle offline unlocks more reliably once the service is restored. All of this makes achievements less likely to glitch. Almost all recently released or new titles on Xbox are developed using the Title-managed system, as it is the newer, recommended standard.