Season Characters, Chests, and Runic Words
And no, you can't do runic words 2.4 in non-seasonal mode and remember to empty your temporary chests on Diablo 2!
Transfer seasonal characters and chests to non-seasonal
At the start of Diablo 2 Resurrected Season 2, all characters that were in Season 1 became non-seasonal and joined your other characters. All items are also transferred and you will be able to access your old chests via a small icon on the current chests. You will only be able to remove items from these temporary chests, which will last for the entire next season, in this case Season 2.
Runic words season 1 and 2
The question arose during all the months before the arrival of the season, the possibility of creating the new runic words in non-seasonal mode. All the season 1 runewords, Fog, Unwavering Will, Obsession, Bane, Flickering Flame, Wisdom, and Pattern are impossible to do in non-seasonal mode and therefore become exclusive to Season 2.
Runic words season 1, 2 and 3
Runic Words are exclusive to Season 2 simply because Blizzard hasn't added any new ones. For Season 3, if they add any, Season 1 then Season 2 runewords will be available in non-seasonal mode, with Season 3 runes exclusive to the season and so on.
source: PezRadar reviews
So be very careful not to do the seasonal runic words in the off season and to remove your items from the temporary chests so as not to lose them!
By Alchemists, October 2022
