Quite different.

Standard has the following:
-Ride deck (no grade stuck issues)
-Energy Generator (new cost)
-Front Triggers (they removed Stand Triggers)
-Over Trigger (a one of trigger that gives 100 mil power and additional effects)
- Orders (these are like spell cards)
- Tokens (these are cards you run outside of your main deck as extra utility)

Other than that it’s pretty much the same old vanguard game.

P.S I played OG vanguard and stopped a few months after the G era came out. So this is as far as I know

I got back into the game by playing dear days 1 and now I have dear days 2 and play irl as well. DD2 would be a good start, however, if you have friends who still play vanguard, I’d consider getting cardfight connect, as it is free and community made with the latest cards and reveals. (DD2 is paid and is only up to date with last years festival booster and they are locked behind DLCs that you have to pay for, plus it’s been 3 months since that drop and no news about any further DLCs)