Karl Marx argued in The Communist Manifesto for the abolition of all nations:
The Communists are further reproached with desiring to abolish countries and nationality. The working men have no country. We cannot take from them what they have not got.
Signet Classics edition of The Communist Manifesto, by Karl Marx and Friedrich Engels, with an Introduction by Martin Malia and a New Afterword by Stephen Kotkin, p 89
Marx argued three pages later for punishing international emigration:
…in the most advanced countries, the following will be pretty generally applicable.
Signet Classics edition of The Communist Manifesto, by Karl Marx and Friedrich Engels, with an Introduction by Martin Malia and a New Afterword by Stephen Kotkin, pp 92-93
…
4. Confiscation of the property of all emigrants….
So, Karl Marx did not believe in nations but did believe in punishing those who emigrated from a nation.
Did Karl Marx want nations abolished, or not? You decide. He couldn’t!