previous episodes

[Seraphim]

Is there any way i can get wapons like choir of one from previous episodes or ice breaker for example ? (currently i have all the expansions of D2)

[Titanica (MAGA) (MASA)]

Yes! The Monument to Lost Lights. It's in the Tower between the Vault terminals in the Courtyard. It has all exotic weapons whose quests or seasons were deleted.

[EckyThump]

For those two specifically, you need the Final Shape Annual Pass which will let you get Choir of One (only way to get an Episode: Echoes pass) and Ice Breaker requires the Final Shape Dungeon Key - which is included in the annual pass edition.

[Kylito]

Choir is in the Episode: Echoes Act 3 questline, Icebreaker is an RNG drop from the final boss of Vesper's Host, and there are triumphs that boost your drop chance.