2023 rookies through August 29.

Players: no pitchers.

https://stathead.com/tiny/1srsy

For single seasons, in 2023, Qualified for league batting title, a rookie, in the regular season, requiring:

Wins Above Replacement (WAR) >= 0 and

Offensive WAR (oWAR) >= 0 and
Defensive WAR (dWAR) >= -10 and
Adjusted OPS+ >= 0 and
Home Runs >= 0 and
Stolen Bases >= 0,
sorted by descending Wins Above Replacement (WAR).

Rk	Player	WAR	OPS+	HR	SO	SB	oWAR	dWAR	Age	Team	Lg	G	PA	AB	R	H	1B	2B	3B	RBI	CS	BB	BA	OBP	SLG	OPS	TB	GIDP	Pos
1	Corbin Carroll	4.9	140	23	101	40	5.0	-0.4	22	ARI	NL	128	524	456	96	128	72	25	8	65	5	51	.281	.362	.522	.884	238	5	*789/HD
2	Gunnar Henderson	4.6	121	22	129	9	3.4	1.6	22	BAL	AL	121	489	434	76	109	61	20	6	65	2	49	.251	.329	.477	.806	207	8	56D/H
3	Anthony Volpe	3.4	88	19	133	20	1.9	2.3	22	NYY	AL	131	486	435	51	94	56	15	4	54	5	44	.216	.293	.400	.693	174	9	*6/H
4	James Outman	2.6	114	17	145	14	2.7	0.1	26	LAD	NL	122	453	386	68	98	64	14	3	59	2	54	.254	.358	.438	.795	169	2	*87/H9D
5	Spencer Steer	2.4	115	18	111	11	2.6	-0.6	25	CIN	NL	129	547	478	60	128	77	31	2	72	2	56	.268	.353	.454	.807	217	7	357/D4H
6	Josh Jung	2.3	119	22	135	1	2.7	-0.1	25	TEX	AL	109	461	427	70	117	70	24	1	67	3	28	.274	.323	.489	.813	209	6	*5/H
7	Ezequiel Tovar	1.9	83	15	133	8	1.1	1.5	21	COL	NL	124	494	465	65	119	73	28	3	61	5	21	.256	.292	.426	.718	198	9	*6
8	Triston Casas	1.6	126	21	110	0	2.0	-1.0	23	BOS	AL	118	441	376	57	97	56	18	2	53	0	62	.258	.363	.484	.847	182	7	*3H/D
9	Masataka Yoshida	1.3	115	13	61	8	1.9	-1.3	29	BOS	AL	117	495	454	65	134	90	28	3	62	0	32	.295	.349	.456	.805	207	18	7D/H

Provided by Stathead.com: View Stathead Tool Used
Generated 8/30/2023.

Four NL, five AL. WAR is a total. It would appear that among non pitchers, the top two would lead their respective leagues as Rookie of the Year candidates. They also lead in oWAR. Volpe leads in dWAR but is tied for second lowest in oWAR and is second lowest in rate (average) stat OPS+.

Only Yoshida, who played several years in Japanese professional leagues, has fewer than 100 SO. He also has the fewest HR. He is the oldest of the nine,

Playing only one fielding position:
SS: Volpe and Tovar
3rd: Jung
1st: Casas.

AAA PA and OPS:
Carroll: 155 .943
Henderson: 295 .894
Volpe: 99 .718
Outman: 251 1.018
Steer: 336 .834 (approximate for two teams)
Jung: 262 .970 (approximate for two teams)
Tovar: 23 .868
Casas: 359 (two years) .862 (approximate for two teams)
Yoshida: 3,251 .957 Seven years in Japan.

Tovar is the youngest and had the fewest AAA PA, although Volpe also had fewer than 100. Maybe both should have started the season in AAA as they are the only two of the nine with OPS+ lower than 100, which is MLB average. Volpe had by far the lowest OPS at AAA. Other than his 19 home runs, he has not done much in the batter's box.