When in a function folder, the rotation to 270 degrees doesnt work.

Try it out with this :

#Rotation 0
setblock ~ ~ ~ minecraft:structure_block[mode=load]{metadata:"",mirror:"NONE",ignoreEntities:0b,powered:0b,seed:0L,author:"Lastphysics",rotation:"CLOCKWISE_0",mode:"LOAD",showboundingbox:0b,integrity:1.0f,showair:0b,sizeX:10,sizeY:0,sizeZ:25,posX:0,posY:0,posZ:0,name:"minecraft:igloo/igloo_corner"}
setblock ~ ~1 ~ minecraft:redstone_block
#Rotation 90
setblock ~ ~2 ~ minecraft:structure_block[mode=load]{metadata:"",mirror:"NONE",ignoreEntities:0b,powered:0b,seed:0L,author:"Lastphysics",rotation:"CLOCKWISE_90",mode:"LOAD",showboundingbox:0b,integrity:1.0f,showair:0b,sizeX:10,sizeY:0,sizeZ:25,posX:0,posY:0,posZ:0,name:"minecraft:igloo/igloo_corner"}
setblock ~ ~3 ~ minecraft:redstone_block
#Rotation 180
setblock ~ ~4 ~ minecraft:structure_block[mode=load]{metadata:"",mirror:"NONE",ignoreEntities:0b,powered:0b,seed:0L,author:"Lastphysics",rotation:"CLOCKWISE_180",mode:"LOAD",showboundingbox:0b,integrity:1.0f,showair:0b,sizeX:10,sizeY:0,sizeZ:25,posX:0,posY:0,posZ:0,name:"minecraft:igloo/igloo_corner"}
setblock ~ ~5 ~ minecraft:redstone_block
#Rotation 270
setblock ~ ~6 ~ minecraft:structure_block[mode=load]{metadata:"",mirror:"NONE",ignoreEntities:0b,powered:0b,seed:0L,author:"Lastphysics",rotation:"CLOCKWISE_270",mode:"LOAD",showboundingbox:0b,integrity:1.0f,showair:0b,sizeX:10,sizeY:0,sizeZ:25,posX:0,posY:0,posZ:0,name:"minecraft:igloo/igloo_corner"}
setblock ~ ~7 ~ minecraft:redstone_block

Should give you this : (see picture)