They have longer life spans which means they don't reach old age at the same rate yes they age differently in the fact that there bodies don't being to break down as early the average human life span in one piece is probably at best 90s with Kureha being an outlier they live longer and their bodies age slower but that's not the same as saying Loki can't have a kid because he's only 20 in some weird giant to human conversion
63 years is 63 years mentally and physically he may be equivalent to a 20 year old but chronologically and Biologically he's 63
63 years is 63 years mentally and physically he may be equivalent to a 20 year old but chronologically and Biologically he's 63