Your friend can join your match from another system. That does not automatically mean your own character, purchased items or campaign save will follow you if you move to that system. Crossplay and cross-progression solve different problems.
Epic’s cross-platform multiplayer guidelines describe crossplay between PC storefronts. This illustrates why the precise scope matters: “cross-platform” on a product page is not necessarily a promise covering every console, mobile version and PC release.
Read the feature as a set of questions
For multiplayer, ask which platforms can share a session, whether the mode you want is included and whether friends need a particular account system. For progression, ask which saves or account items transfer and whether a supported linking procedure is required.
Then check ownership separately. Access to an account’s progression is not necessarily a licence to run the game on a second platform. Epic’s guidance on games across platforms explains that purchases are generally tied to their respective platforms, with particular products having their own arrangements.
Currency, add-ons and platform-specific rewards can have exceptions even when core progression is shared. The game’s current support page is a better guide than a friend’s experience with another title.
Before linking, identify the account you want to keep
Write down the account that holds your existing progress and read any warnings about unlinking, replacement or merging. Do not assume that two separate saves can be combined. If the instructions are unclear, stop before confirming a change that could affect access.
A practical comparison note might contain four lines: play together, carry progress, own the game, and transfer purchases. Mark each with the supported platforms and the source date. This makes an attractive but vague feature label much easier to evaluate.
For a group planning its first session, test invitations in the intended mode before everyone commits to a long campaign. A successful crossplay test answers the multiplayer question; it still leaves the separate account and progression checks worth doing.