IELTS and PTE both are used for testing our proficency in English.IELTS is international relevance and it acceptable all over the world.But PTE is not acceptable it has certain limitation in ceryace countries.PTE is mainly good for Australia.

While considering the difficulties I think PTE is much more simpler than IELTS since PTE is computer based examination while IELTS is human based and also people are getting better score in PTE.

But the main factor we have to consider is our language proficiency.If our language is good then we don't have to worry about These two exams.

Good luck