This article talks about how Oneness and Trinity should agree to discuss their differences civilly. I pasted a short section below. The whole article is much bigger.
One point of tension between Trinitarian and Oneness Pentecostals has
been the claim by some on the Oneness side that Trinitarians believe in three
gods. On the other hand, some on the Trinitarian side have asserted that
the Oneness view is the ancient heresy of Sabellianism reborn. Th e Trinitarian
team affi rms, “We as Trinitarian Pentecostals wish to stress that we believe in
One God and not in three gods. According to Trinitarian dogma, ‘Father, Son,
and Holy Spirit’ are not three ‘separate’ or in any way ‘divisible’ persons but
rather three distinct but inseparable persons of one divine nature.”11 Dialogue
will be enhanced and the Golden Rule will be obeyed if both Onenessand Trinitarian Pentecostals refrain from claiming that others believe something
they deny. It is doubtful if any Trinitarian Pentecostals have ever professed
to believe in three gods, and Oneness Pentecostals should not claim
that they do.12 On the other hand, Oneness Pentecostals do not embrace
the sequential modalism of Sabellianism, and Trinitarian Pentecostals should
acknowledge this.13