Answer:
Antonym- remain, separate, part Part of speech-Verb.
Step-by-step explanation:
If you mean cross as in intersect, the opposite isn't clear. It could be parallel, separate or part, but each aren't exact opposites.
If you mean cross as in angry, one antonym could be happy.
If you mean it as moving through an area, one antonym could be remain.
If you mean it as blend, one antonym could be divide.
If you mean it as in hinder, antonyms could be to support or to abide.
As for the part of speech,
1. Verb
2. Adjective
3. Verb
4. Verb
5. Verb
Hope this helps.