not sure. a cursory look at the specs says that it has 3 of the 4 LTE bands for Verizon, but it's missing Band 13 which is a pretty critical LTE band (the 700 MHz band). It seems to have B0 of CDMA which I think would be 1x (2G), so it could potentially fall back to that in a poor LTE area. BUT, it's up to Verizon to work get the bands the phone does have running on it's network. The HTC U11, for instance, has band 4 but is currently not able to access it on Verizon's network HTC is working with Verizon to get band 4 (XLTE band) up and running on the U11.
Bands (OnePlus 5)
FDD LTE: Band 1/2/3/4/5/7/8/12/17/18/19/20/25/26/28/29/30/66
TDD LTE: Band 38/39/40/41
TD-SCDMA: Band 34/39
UMTS(WCDMA): Band 1/2/4/5/8
CDMA EVDO: BC0
GSM: 850/900/1800/1900 MHz
Verizon network bands/frequencies:
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