First, thanks to Kevin for his answer to my last question (I can't answer my post, I tried 3 times) about grouping columns from different samples (same individual) in a merged VCF.
The only command that put all positions in same column is
bcftools roh although output is a plain text file with 2 columns to remove, first
ST and second
I think it can be converted to VCF with
bcftools convert --tsv2vcf
EDIT (@RamRS): Added context.