As far as I'm aware there shouldnt be any differences between the two. I'd say buy the phone your budget allows for. Personally I spent more by getting he 256gig model because the storage was worth it to me. So basically my advice is buy older but spend the difference on meaningful storage.
Depending on your threat model you may wish to buy second hand or buying with cash so the IMEI isn't tied to your name.
I initially struggled with the zero google because many apps didn't work. I ran a secondary profile with google services running for those. Recently, due to another comment here on Lemmy I retried those apps (with exploit compatibility on) and most of them worked. So I've ditched the secondary profile. My point being, that most apps will probably work but if they don't you always have the option of a secondary profile.