The game currently runs civs around the time period of 850-1550ish.
Make a Norse Civ (either Sweden, Denmark, Norway, Swedish-Norway union, or something - you guys do the historical research) but have it go as follows:
Age 1 dark age: Vikings (850-890ish Viking raids)
Age 2 feudal age: Vikings (1066ish Viking invasion)
Age 3 castle and
Age 4 imperial: Modern Sweden or Nordic union something along those lines, and if it’s Sweden, have the SWISS PIKES be available age 4. different from spearmen. So maybe age 1 instead of getting spearmen, this civ gets an “axeman” and make the unit behave somewhat anti archer or whatever you think will work best ingame but essentially a shield and axe viking.
And this civ only gets swiss pikemen at age 4, but make them prominent such as best pike and shot (pike prominently) civ.
Still rooting for Spanish civ man, run Spain 850-1550 from muslim ruling of spain to reconquista Christianity overthrowing islamic spain into Tercio formations age 4 pike n shot era
Why not do the research yourself and build a complete timeline. It’s fun assuming you love the faction and don’t mind doing some work. Also why are we bound to your timeline.
Make the civilization as either Danes, Norway, or Sweden. Make Vikings, a light raiding infantry unit which can construct transports without the need for a dock.
What? Swiss pikes? You mean the group of people located near France, Germany, and Italy? Those elite mercenaries would have much more in common with the HRE vs a nordic faction. If you want a unique unit for Sweden, perhaps Gotland has you covered. With a Nordic war merchant or some other made up unit like what total war did with the Gotland Footmen. https://wiki.totalwar.com/w/Gotland_Footmen_(M2TW-K-TC_unit)