The XS series has various modes that can allow you to adjust and span across multiple screens. In the XS Series you have the following: SPAN-2, SPAN-3 and SPAN-4 capabilities.
So essentially you can do a 2x3 video wall; but you will need two XS-83H units. Or you can do a 3x4 video wall; you will need 3 XS-84H units. Then in the MENU go to > 2: VIDEO OUTPUT go to > then use the “MANUAL SIZE V” and “POSITION V” to adjust the image and position. Aside from these adjustments you do have the Bezel compensation that you can use to adjust for the borders.
This is quite a tedious task that you will want to make sure that you save in your presets so that you will not have to dial in the set up next power up.