I don't know if it will be under the filesize limit for itch.io's server (1gb), the beta was over 900mb already and I've added more render and animations since then.
I believe, from my own experience with many other AVNs here on Itch, that the limit is likely a flat Gig. All games I've seen that tip over it end up usually being hosted for download on Mega.NZ. But that's just my two cents and supposition via my experience as a player, not a dev. :)