In general the requirement to support IPv6-only networks does not affect your server infrastructure. See FAQ #3 of the above-mentioned pinned post.
However, once you start messing around with NAT traversal technologies, you’ve definitely fallen off the beaten path and that engenders some risk. In theory NAT64 should work with NAT traversal technologies [1] but if I were in your shoes I’d feel a lot happy having tested it.
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[1] Here’s a quote from RFC 6146:
NAT64 is compliant with the recommendations for how NATs should handle UDP [RFC4787], TCP [RFC5382], and ICMP [RFC5508]. … Because of the compliance with the aforementioned requirements, NAT64 is compatible with current NAT traversal techniques, such as ICE [RFC5245], and with other NAT traversal techniques.