Finally got it.
# variants are set up as chr1:1000:A:G
ht = hl.Table.from_pandas(variants)
ht = ht.key_by(**hl.parse_variant(ht.variant))
mt_filtered = mt.filter_rows(hl.is_defined(ht[mt.row_key]))
Finally got it.
# variants are set up as chr1:1000:A:G
ht = hl.Table.from_pandas(variants)
ht = ht.key_by(**hl.parse_variant(ht.variant))
mt_filtered = mt.filter_rows(hl.is_defined(ht[mt.row_key]))