O.o this is a really odd question given way the damage types actually work.
Kinetic does 200% damage to shields, 50% damage to armor
High Explosive does 200% damage to armor, 50% damage to shields
Energy damage does 100% damage to all types
Surely the solution to your one-size-fits-all weapon is Energy damage
A weapon that does:
100 Kinetic
100 High explosive
would do 250 damage to Shields,
and 250 damage to armor
So simply make it an energy weapon that does 250 Energy damage and your problem is solved.
However if that's not to your taste the
Blackrock mod has a weapon called the "Shard Autocannon" which does Kinetic damage with some under-the-hood modifier -
that I in no way understand - that gives it a chance to do significant damage vs armor/hull, maybe you can take a look at that.