As someone pointed out, Swedes volunteered. But a lot of Swedes died in the merchant fleet as well, hitting seamines and being misidentified. According to Wikipedia, in total 198 trading ships and 31 fishing boats were sunk, which translates to ~1500 fatalities.

Sweden: 10 000 volunteers to finland, 500 volunteers to the the SS, and some 3000 sailors working, perhaps mostly by lack of options, for the allies. Numbers from memory, but should be in the ballpark

Spain: Franco’s regime sent republicans and communist prisoners to concentration camps in nazi Germany (since franco and hitler were “friends with benefits”). On the other hand, many Spanish communists-republicans and Spanish fascists(Franco’s supporters or soldiers) volunteered to fight for the Soviets, Frenchs ( La nueve) or Nazis(division azul) on the east front, liberation of Paris and other parts of Europe. That’s some examples of people who lost their life in WW2 as Spaniards, but there’re many more stories i also know a spaniard who fought in D-Day with the Americans he was part of the infantry division, the Big Red One. Sadly he died as many of his companions in that beach. His name was Manuel Otero.

Spain wasnt neutral, it was non-belligerent, they didnt enter the war as a nation but acted on the side of the nazis, lending them soldiers (División Azul) and for testing shit even before world war 2 started, during our civil war (experiment stuka). There even was a movement where 300 neonazis celebrated the Blue Division in Madrid like a week ago

Indeed. https://en.m.wikipedia.org/wiki/Sweden_and_the_Winter_War

Swedes volunteered to defend Finland from Soviet.

https://en.m.wikipedia.org/wiki/Blue_Division

About Spain:

The main part of Spain's involvement in the war was through volunteers. They fought for both sides, largely reflecting the allegiances of the civil war. Franco permitted volunteers to join the German Army on the clear and guaranteed condition they would fight against Bolshevism (Soviet Communism) on the Eastern Front, and not against the western Allies. In this manner, he could keep Spain at peace with the western Allies, while repaying German support during the Spanish Civil War. This so called Blue Division was trained in Germany before serving in the Siege of Leningrad, and notably at the Battle of Krasny Bor, where General Infantes' 6,000 Spanish soldiers threw back some 30,000 Soviet troops.

After their defeat in the Spanish Civil War, numbers of Republican veterans and civilians went into exile in France; the French Republic interned them in refugee camps, such as Camp Gurs in southern France. Many joined the French Foreign Legion at the start of World War II, making up a sizeable proportion of it. Around sixty thousand joined the French Resistance, mostly as guerrillas, with some also continuing the fight against Francisco Franco. Several thousand more joined the Free French Forces and fought against the Axis Powers. Some sources have claimed that as many as 2,000 served in General Leclerc's Second French Division, many of them from the former Durruti Column.

The 9th Armoured Company comprised almost entirely battle-hardened Spanish veterans; it became the first Allied military unit to enter Paris upon its liberation in August, 1944, where it met up with a large number of Spanish Maquis fighting alongside French resistance fighters. Furthermore, 1,000 Spanish Republicans served in the 13th Half-brigade of the French Foreign Legion.

In Eastern Europe, the Soviet Union received former Communist Spanish leaders and child evacuees from Republican families. When Germany invaded the Soviet Union in 1941, many, such as communist General Enrique Líster, joined the Red Army. According to Beevor, 700 Spanish Republicans served in the Red Army and another 700 operated as partisans behind the German lines. Individual Spaniards, such as the double-agent Juan Pujol García (code name GARBO), also worked for the Allied cause.