Information

Minecraft version: 1.15.2
Environment: Singleplayer / Multiplayer

Mod name: Nether Portal Spread

Question

Can we change the spread to change blocks into blocks from mods (ie stone into Soulstone from Mystical Agriculture)?

Sorry for the late reaction, but yes you can! The format works like modid:blockid. Example with Soulstone from Mystical Agriculture:

I've also added it to the description of the mod:
https://www.curseforge.com/minecraft/mc-mods/nether-portal-spread