What do you plan on shooting? Portraits, landscapes? or is it for mostly video. Is this a main work horse or a camera used as a to fulfill a hobbie? Full frame lens's are quite pricey compared to apsc. I know you can crop down to use apsc len's on full frames but feel like defeats the whole purpose. I enjoyed my 18-105mm paired with my a6500. Super versatile. Pretty sure the equivalent is the 24-105mm. With a price tag of $1400 tho idk if that's in your budget.
I only shoot stills but my all-time favourite is a Nikkor 50mm f/1.4 on an adapter. Close second is the MF Tokina 20mm f/2. Excellent glass and not too hard on the wallet.