@Thenomain
For blood, It's on a per-session basis typically, with blood only really mattering at session start and throughout. If you're running over a full multi-day event, like a big convention, starting blood is usually pre-determined (because running starting blood for 900 vampire players is undoable).
For willpower, a session with always start out full and then dealing with Virtue/Vice or other methods of recovery during game.
For blood...
Laws of the Night has a chop that's thrown; success is full, tie is half, lose is 3, further modified by Herd and other , with hunting tests done in game with 'you can take X blood safely, Y blood dangerously, or kill a human for their max blood value'.
NWoD MET the 'default' is 'at start of game roll a d10/draw a card, to show how much blood you have' and then alter it with Herd. I've only seen one LARP ever use that RAW and it was not a good setup. Most games devised their own method for starting blood (we used a BP and other factor formula). For multi-day events, STs enforce keeping track of Blood, use of Herd and feeding checks to keep track of that, so if you end Friday with 4 Blood you start Saturday with 3 (barring corner cases like Coil of Blood).
BNS MET functions assumption of Herd and downtimes. Unless you have a dot of Herd or submit a feeding downtime, or have a related power such as Animal Succulence, you start with half blood. If you have Herd or used a downtime to feed, you come in at full. This is further modified by ST adjustments, such as feeding difficulty levels (making it require more dots of Herd to come in at full or more downtimes put towards it). In game, you take 15 minutes out of game to get 2 blood; or, if you have Herd, you take 5 minutes out of game and gain your Herd in blood, OR an ST can run a feeding scene (though we keep these to a bare minimum).
For willpower..
Laws of the Night doesn't have a WP recovery through play mechanic that I can recall, or find with a quick skim. You have WP based on your Generation, a starting/max, and WP starts refreshed at the beginning of each session.
NWoD MET functions like tabletop; sleep or Virtue/Vice refresh.
BNS MET has WP start at max at session start, and STs or players can offer a WP refresh (STs at any time except combat, players once per session per person except in combat) for good RPing. Otherwise, WP can change over the course of a multi-day event, depending on factors; generally a full day of rest (or night of rest for mortals) recovers WP completely.
So not really suited for a MU* as, while lots of MET games (particularly large chronicles like the Camarilla/Mind's Eye Society) have shit going on all the time, it's handwaved typically unless it's at an event, where that stuff is more kept track of.