This question is impossible to answer satisfactorily since it requires stereotyping, generalization and oversimplification. If you search the forums for key words like "boyfriend" "girlfriend" "relationship" etc you'll find various past discussions, opinions and experiences about this.
The biggest issue I found was communication. If you are unable to express your deepest thoughts and emotions to a love interest due to a language barrier , it makes things very difficult. Part of a good relationship is strong communication between partners. Having to use a third party translator or a dictionary to get your meaning across in day to day conversation is difficult.