Your airline you are flying with has the last say.
Check with them first and get it in writing if they say OK.
AirTags rely on proximity to Internet connected Apple iPhones and BlueTooth on those phones being switched on to send their location updates, so you may not have reliable information if there aren't any around.
Unique markings on your suitcase will prevent the confusion of somebody accidentally picking up a suitcase which looks identical to theirs, and will possibly deter thieves if you can spot your gaudy marked suitcase across the terminal being wheeled out by a suspicious type. Sure, back this up with an embedded AirTag discreetly hidden.
Best be waiting at the baggage collection point as the suitcases come rolling out, then you have a better chance of spotting yours before somebody is tempted to walk off with it.