Setup NAPT for Dual WAN IPv6

[Hikari]

Hello! Sorry for so many posts, I think it's better to use 1 thread for each question and on proper forum.

So, I have 2 ISPs and both insist on providing /64 global prefixes. I had complained on both and one of them (NET/Claro) even said that only government companies are forced to follow IPv6 standards while private ISP companies can use "proprietary" protocols and it's my problem if something doesn't work and "welcomed" me to cancel their service "if I wish to". Yeah.

I think the only solution for that would be to use NAPT for IPv6?

I think I'd have to choose one /60 prefix inside one of their /32 prefix, even though they aren't providing this /60 to me, because I need a public one for devices to choose IPv6 instead of IPv4. I'd be unable to connect to anyone inside this /60, but I never connect to any residential IPs other than mine anyway.

Would that work? or is there a better way to setup NAPT and Dual WAN when ISPs provide only /64 global prefixes? lol