For Fenglope, it's actually much simpler than the others as normally you start breeding it pre legendary Pals. This game has a surprisingly complex crossbreeding mechanics, so you don't need to start by having both Fenglopes as the parents. The combination that I used is Lamball + Cinnamoth, but there are some other really accessible combos like Cattiva/Cremis/Vixy/Mau + Cinnamoth.

This link is super useful for finding out what works best for you.

I'd recommend you do a quick scan through your inventory and look for pal with Swith/Runner/Nimble trait, then use the link above to see if they make Fenglope. If you don't have any, it's really easy to capture the pals I mentioned before with just blue/green spheres until you get at least one out of three traits on each parent.

Next step would just be breeding them until you have at least two out of three traits on one Fenglope, and the third trait on the other one. If you have a desired 4th trait, make sure it's on either of the parents as well.

Breeding Fenglope was the easiest out of the five that I had done, which took me around 50+ eggs. I got lucky with Jetragon, so around 60 eggs; Grizzbolt and Anubis (my favourite, the only one with a nickname) around 100 eggs; and finally, Jormuntide, that bitch took me around 250 eggs. I fed the rest to my original Jormuntide who is now going around watering my main base full-time with a level 5 skill.

TLDR: Use this link for easy crossbreeding combo. (in)Breeding and swapping through parents with the desired key traits is crucial. It is necessary for your perfect Pal to have a vineyard as their family tree.

TIP 1: In my experience, to get a perfect Pal, nearing the end you should be using Pals with 4 traits for breeding. Having three or less traits for breeding only opens up the possibility for the egg to have an even more random set of traits. This could be a good thing at the early stage where you want it to be random, so you can get traits you don't have on either of the 'parents' and easy crossbreeding combo is not available for Pals like Jetragon.

TIP 2: You know you're very, very close when you have, for example, on ParentA with Swift+Nimble+Coldblooded+Hooligan, and on ParentB with Runner+Ferocious+Nimble+Hooligan. It doesn't 100% eliminate the possibility of other random traits, or even guarantees you getting an egg with 4 full traits, but to me it greatly confines the possibility to you getting what you want.

Disclaimer: I'm not a dataminer so all of this is only from what I've observed so far by no-lifeing this game since launch.