The rather humorless face主// possessed谓// 宾a quiet dignity, with a long goatee pointing down like a compass needle.

with /a long goatee/ pointing down like a compass needle是with的复合结构，形式是【with+n.+现在分词】，整体作句子的伴随状语

It主 //was系//表 the sort of face (that age would lend roundness, but not necessarily kindness.)

括号部分是定语从句修饰先行词face，还原定语从句=> age would lend that face roundness, but not necessarily kindless

lend sb sth指的是“给……增添……“，在这里就是说年龄的增长可能会让这张脸变得越来越圆润，但并不会增添丝毫仁慈。

尝试翻译一下，还请老师同学指正！

那张脸没有一丝幽默感，还带有一种安静与沉稳，长长的山羊胡子像指南针一样向下直指。年龄的增长可能会让这张脸变得越来越圆润，但并不会增添丝毫仁慈。

The rather humorless face possessed a quiet dignity, with a long goatee pointing down like a compass needle. It was the sort of face that age would lend roundness, but not necessarily kindness.

参考译文：那张非常严肃的的脸具有一种安静的高贵，长长的山羊胡子像指南针一样朝下翘着。这是一张随着年龄增长而显得圆润的脸，但未必是一张善良的脸。

为了方便提问者理解，我先把句子省略部分补充完整再进行语法结构分析供网友参考

The rather humorless face【主语】// possessed 【谓语动词】//a quiet dignity【宾语】//, with a long goatee pointing down like a compass needle【后置定语】. It【主语】 //was 【系动词】the sort of face 【表语】//that age would lend roundness, but that age would not necessarily lend kindness【后置定语】.