Short-term visitors have more options than they realize. The simplest is your hotel or serviced apartment: with the front desk's agreement, parcels addressed to you as a guest work fine for most needs. A trusted friend's or relative's address is the next easiest and is what most people actually use for anything official-looking.
Beyond that, the courier networks themselves help: many offer hold-at-location, letting you ship to their depot or a partner shop and collect with ID. Parcel locker networks are widespread in many countries now and often accept registrations without proof of address. Coworking spaces frequently include mail handling with a membership, which doubles as a professional address.
For something more durable, virtual mailbox services give you a real street address that receives, scans and forwards mail, and traditional PO boxes remain available at post offices, though some countries require local ID or residency paperwork to rent one.