I guess we'll see how this plays out when it actually opens, but this is the text on the DL Oga's webpage:
Checking In
Guests should check in no earlier than 15 minutes prior to their reservation time with the Cast Member at the end of the queue at Oga’s Cantina inside
Star Wars: Galaxy’s Edge.
If the virtual queuing system is being used, Guests with reservations for Oga’s Cantina may enter the land up to one hour prior to their reservation time at the Fantasyland entrance to Star Wars: Galaxy’s Edge.
Each person in your party must be present upon check-in and for admission to the land and the cantina. Please be prepared to present your reservation confirmation, photo ID and the credit card provided at the time of booking.
Guests will be admitted as soon as space that accommodates their party size becomes available. Late arrivals may not be accommodated.
Limited Seating
Oga’s Cantina consists mainly of standing room, with limited seating. Seating is not guaranteed upon entry, separate parties may be seated together and large parties may be separated.
Alcoholic Beverages
Guests must be 21 years of age or over to consume alcohol; valid photo ID is required. There is a maximum of 2 drinks per Guest.
Snacks
A limited menu of snack offerings will be available.
I would guess they would be handled similarly since it took them a couple weeks of trying different lines/reservations/text returns/etc to get a system that works fairly well and doesn't involve hours of standing in line. I tried to look at the WDW page to see if it had similar language, but I just get the Falcon.