The linked video DOES NOT demonstrate this build, this build is a generic condition overload melee build which works well with status proc primaries/secondaries. You don't need [Gram Prime] and you don't need these exact mods, its just an example.
A sample melee build to run with my Umbral [Eternal War] [Valkyr] Build.
Ideally, you'd really want a riven for this build so you can fit in other stats and preffered mods ([Primed Reach], [Life Strike], etc.) Any stat on the riven that eliminates the need for another mod in this build is helpful (crit chance would get rid of [Sacrificial Steel], crit damage replaces [Organ Shatter], attack speed replaces berserker, elementals replace primed fever strike, combo duration replaces drifting contact, etc.)
Umbral Eternal War Valkyr Build: https://overframe.gg/build/1042/
Sample Status Proc Weapon: https://overframe.gg/build/1051/