In his debut season at the French club, the winger registered four goals and eight assists across 27 Ligue 1 appearances.
His performances did not go unnoticed, and in May reports emerged that Manchester United had shown interest in the winger.
Those reports have since been overtaken by developments in Germany, with Bayer Leverkusen moving to complete a deal for the player.
According to multiple reports, Leverkusen and Lyon have now reached a full agreement over Moreira's transfer, with a medical expected to follow shortly.
The fee is reported to stand at around €30m, including bonuses, with Moreira set to sign a contract running until the summer of 2031.
Lyon are understood to be under pressure to secure a significant transfer fee before the end of June, in order to satisfy financial oversight rules in French football.
That deadline is reported to have strengthened Leverkusen's negotiating position throughout the talks, with the German club said to have moved swiftly once it became clear a deal could be struck.
Moreira has been a regular for Portugal at Under-21 level, and his rapid rise since arriving in France has fuelled growing interest from clubs across Europe.
The winger began his career at Sporting Lisbon, working through the Portuguese club's academy before making the move across to Ligue 1 last year in search of regular first-team football.
That decision appears to have paid off quickly, with his performances for Lyon catching the eye of several clubs well beyond France's borders.
The move would represent Leverkusen's second significant signing in a matter of days, following the arrival of a new head coach at the Bundesliga club this summer.
Leverkusen's recruitment strategy this window has focused heavily on bringing in younger, versatile attacking players capable of operating across multiple positions, a profile that fits closely with Moreira's game.
For Lyon, the sale offers a route to balancing their finances ahead of a looming review by French football's financial watchdog, even as it means losing one of the breakout performers of their season, with the club already believed to be lining up potential replacements.