This. They also need to find ways on keeping the exotic quests and catalysts that will disappear.
Legend of Acrius (Leviathan)
Tarabah (Crown of Sorrow)
Rat King (Titan)
Bad Juju (Tribute Hall, Leviathan)
Polaris Lance (Mars)
Sleeper Simulant (Mars)
Whisper of the Worm (Io)
Truth (Menagerie)
Worldline Zero (Mars)
Legend of Acrius Catalyst (Leviathan)
Sleeper Simulant Catalyst (SoS)
Skyburner’s Oath Catalyst (Leviathan)
Telesto Catalyst (EoW)
Huckleberry Catalyst (Mars)
Whisper Catalyst (Io)
Worldline Catalyst (EP)
The Catalysts are fairly easy. Acrius can be placed as a Nightfall Ordeal reward for the Armsdealer Strike. Sleeper can be a reward from Rasputin. Skyburner’s Oath can be from the Insight Terminus Ordeal Nightfall. Telesto can be from the Corrupted Ordeal Nightfall. Huckleberry can be found in any Heroic Story mission. Worldline can progress by damaging Hive bosses in the open world. Whisper can have the mission left in or have it drop from some other activity.
The weapon’s themselves are all quest weapons. Bad Juju may be preserved if they keep/move the tribute hall. Tarabah can just have its drop location changed. The rest have steps on locations that won’t exist.
Never bothered trying for the sleeper catalyst. Could never get the SMG to drop from EP. Heard the 'reprised' version of it doesn't count for the catalyst anyway, so I'm not worried.