Not really. For Glory is completely different than live tournaments for a variety of reasons.
1. Some characters thrive in lag more than others. For example, some characters like Samus and Zelda do pretty well online because they can throw out moves that are not that safe and lag makes it harder to punish certain things. Offline these are two of the worst characters in the game. Likewise, Sheik is widely considered the best character, but she's very difficult to play online because of her precise timing. So you might be able to destroy sheik's online, but meet one IRL and it's a whole different story. Falco is actually better online than offline, because of his decent frame data allowing him to sneak in attacks that wouldn't otherwise work.
2. For Glory is all Omega stages. In tournaments you'll have to deal with stages like Town and City and Duck Hunt, which are a completely different dynamic and benefit certain characters way more.
3. For Glory players are more likely to play "their favorite character" rather than the good characters. Online, you might find lots of Kirbys, Little Macs, and Links, but in a real tournament, you're much likely to see lots of Diddys, Sheiks, Marios and ZSS. Now of course there are some high tiers that are popular online, like Yoshi and Sonic, but overall you'll lack practice against the characters for whom you need it the most.
4. And then of course, the skill level is just way lower on For Glory. The biggest thing I noticed is that people online are terrible at edgeguarding. Some of them don't even try to do it. When you play Falco against competent players, you start to learn very quickly how bad his recovery is.