For severely neglected trees, nearly any fertiliser should get a response.
I would probably first go for a low to medium N, organic based, to give some soil microbe stimulation. Or at least include some soil stimulation.
As for pruning, you may as well remove any damaged growth etc, rather than resurrect the tree with it still there.
For plants with previous heavy leaf loss, maybe prune back the top third, especially naked twigs, rather than trying to get every bud to flush.
Sometimes heavy flushing on tired plants leads to growth stagnation.