The negative evaluation/score for Black at the beginning of the game is based on komi of 7.5 points. Leela Zero has this hardwired (along with Chinese rules) and cannot be adjusted. Katago has been trained on variable komi and different rule sets. It can have the rule set adjusted in the config file. The komi can be adjusted through whatever client you are using. If you load a game with komi 6.5, katago will read this in the sgf file but LZ will ignore it AFAIK.
If you set the komi to 5.5 or lower in katago, the evaluation and score on the empty board favor Black.
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Dave Sigaty"Short-lived are both the praiser and the praised, and rememberer and the remembered..."
- Marcus Aurelius; Meditations, VIII 21