Mojang changed the XY offset, it needs to be specified within the block properties. The FLOWER block property in PropertyUtil needs to add this change. Modded flowers that use this property don't have the correct XY offset.

The FLOWER property is currently written as:
public static final Block.Properties FLOWER = Block.Properties.of(Material.PLANT).noCollission().instabreak().sound(SoundType.GRASS);

It needs to be changed to:
public static final Block.Properties FLOWER = Block.Properties.of(Material.PLANT).noCollission().instabreak().sound(SoundType.GRASS).offsetType(BlockBehaviour.OffsetType.XZ);