need some help with transport Guardians through the nether

Hey I manage to build a Guardians farm but the spawn rate is lame
so I understand I need to be at high Y level
but How can I transport all the Guardians up to me
I prefer not to do it with just long pipe with soul sand
I want to do it through the nether
the main usage gonna be the EXP I will get ,and not only the loot